OISM to MVPN/PIM interworking non-DR attract traffic function on MEG/PEG

This chapter provides information about the non-DR attract traffic function on Optimized Intersubnet Multicast (OISM) to Multicast VPN/Protocol Independent Multicast (MVPN/PIM) interworking (MEG/PEG function).

Topics in this chapter include:

Applicability
Overview
Configuration
Conclusion

Applicability

The information and configuration in this chapter are based on SR OS Release 24.10.R2. Only on FP-based platforms, SR OS Release 22.2.R2 and later support MEG/PEG non-DR attract traffic.

Overview

SR OS Release 21.10.R1 and later support OISM EVPN interworking with MVPN and PIM networks. Two key interworking functions are used to achieve this interworking:

MEG (MVPN to EVPN Gateway): Bridges MVPN and EVPN.
PEG (PIM to EVPN Gateway): Bridges PIM and EVPN.

The system uses a Designated Router (DR) election process to ensure redundancy. This is achieved by:

Including the Designated Forwarder (DF) Election extended community in the Inclusive Multicast Ethernet Tag (IMET) routes.
Following the DR selection procedures defined in RFC 8584.

After being elected, the MEG/PEG routers use Ingress Replication (IR) to handle multicast (MC) traffic efficiently within supplementary broadcast domains (SBDs).

In addition to IR and only on FP-based platforms, SR OSRelease 22.2.R2 and later also support:

MLDP root-and-leaf (See P2MP mLDP Tunnels for BUM Traffic in EVPN-MPLS Services for more details) on the SBD of the MEG/PEG routers. On a MEG/PEG router, traffic originating from either the MVPN/PIM domain or the EVPN domain can be forwarded or received by the MEG/PEG DR through an MLDP provider tunnel. The PIM Instance can be in MVPN.
non-DR attract traffic

Example topology is used to illustrate the working of the OISM EVPN to MVPN/PIM interworking non-DR attract traffic function on MEG/PEG. This is the same topology as for the OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI.

PE-2 and PE-3 connect an OISM EVPN network hosting PE-5 and PE-6, and an MVPN/PIM network hosting PE-7 and PE-8. PE-2 and PE-3 act as MEG/PEG DR candidates. PE-2 and PE-3 forward traffic into the EVPN using MLDP I-PMSIs. A MC receiver connected to PE-6 in the EVPN network joins MC group 225.0.0.1 of a MC source connected to PE-8 in the MVPN/PIM network to receive MC traffic from the MC source. A MC receiver connected to PE-7 in the MVPN/PIM network joins MC group 239.0.0.4 of a MC source connected to PE-5 in the EVPN network to receive MC traffic from the MC source.

The provider-tunnel inclusive, owner, and ingress-repl-inc-mcast-advertisement are configured as in OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI.

The MEG/PEG DR translates Selective Multicast Ethernet Tag (SMET) routes into PIM routes and the other way around, depending on where the MC source and the MC receiver are located. Even though the MEG/PEG non-DR also receives SMET routes from a MC receiver that is located in the OISM EVPN network, the MEG/PEG non-DR does not execute this action.

# On PE-3#
[ex:/configure service vpls "SBD-8" routed-vpls multicast evpn-gateway]
A:admin@PE-3# non-dr-attract-traffic ?

 non-dr-attract-traffic <keyword>
 <keyword> - (none|from-evpn|from-pim-mvpn|from-evpn-pim-mvpn)
 Default   - from-pim-mvpn

    Multicast traffic attraction option on non-DR router GW

    Warning: Modifying this element toggles
    'configure service vpls "SBD-8" routed-vpls multicast evpn-gateway admin-state' 
automatically for the new value to take effect.

The non-dr-attract-traffic command allows changing the above MEG/PEG non-DR behavior, according to the mode that is selected from the following options:

non-dr-attract-traffic none: the MEG/PEG non-DR does not generate wildcard SMET routes and does generate a PIM/C-multicast join upon receiving a SMET route.
Note: •The non-dr-attract-traffic is changed in SR OSRelease 22.2.R1 in a non-backward compatible manner. When upgrading to SR OSRelease 22.2.R1, the user needs to remove the command non-dr-attract-traffic from the configuration, otherwise the upgrade will fail.
non-dr-attract-traffic from-pim-mvpn (default): backward compatible with the behavior in SR OSRelease 21.10 if non-dr-attract-traffic none was configured before the upgrade. With this option, the MEG/PEG non-DR does not generate wildcard SMET routes but it generates a PIM/C-multicast join upon receiving a SMET route. Local joins on a non-SBD service generate PIM/C-multicast routes or SMET routes irrespective.
non-dr-attract-traffic from-evpn: the MEG/PEG non-DR generates a wildcard SMET route to attract the multicast traffic from the OISM EVPN domain. No layer-3 IFF or PIM/C-multicast route is triggered from received SMET routes on the MEG/PEG non-DR.
non-dr-attract-traffic from-even-pim-mvpn: the MEG/PEG non-DR behaves as if non-dr-attract-traffic from-pim-mvpn and non-dr-attract-traffic from-evpn are configured concurrently.

Configuration

The initial configuration is identical to that for OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI.

The initial configuration includes:

cards, MDAs, ports
BGP route reflector (RR)
router interfaces
IBGP in the EVPN network for the EVPN address family
IBGP in the MVPN/PIM network for the VPN IPv4 and MVPN IPv4 address families
IS-IS on the router interfaces (OSPF or OSPF3 router interfaces are also possible)
LDP and MPLS in the EVPN and MVPN/PIM networks (not on the RR)
VPRN service in the EVPN and MVPN/PIM networks
routed VPLS services in the EVPN network

Router configuration

The router configuration is identical to that for OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI.

Service configuration in the EVPN network

The service configuration is identical to that for OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI.

Use cases

The following use cases are described in the following sections:

MC traffic from MC source on MVPN/PIM network to MC receiver on EVPN network
MC traffic from MC source on EVPN network to MC receiver on MVPN/PIM network

MC traffic from MC source on MVPN/PIM network to MC receiver on EVPN network

MVPN/PIM MC source - EVPN MC receiver example setup illustrates the MEG/PEG non-DR attract traffic function on MEG/PEG for MVPN/PIM to OISM EVPN interworking. This is the same setup as for the OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI for MVPN/PIM to OISM EVPN interworking.

The MC source is connected to PE-8 in the MVPN/PIM network. The MC receiver is connected to PE-6 in the EVPN network. The MC source (198.51.100.21) sends MC traffic to the MC receiver (10.0.4.21) in MC group 225.0.0.1.

Figure 2. MVPN/PIM MC source - EVPN MC receiver example setup

PE-2 is elected as MEG/PEG DR, PE-3 is MEG/PEG non-DR. See OISM to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI for the election procedure.

[/]
A:admin@PE-2# show service id "SBD-8" evpn-mcast-gateway all

===============================================================================
Service Evpn Multicast Gateway
===============================================================================
Type                         : mvpn-pim                
Admin State                  : Enabled                 
DR Activation Timer          : 3 secs                  
Mvpn Evpn Gateway DR         : Yes                     
Pim  Evpn Gateway DR         : Yes                     
===============================================================================

===============================================================================
Mvpn Evpn Gateway
===============================================================================
DR Activation Timer Remaining: 0 secs                  
DR                           : Yes                     
DR Last Change               : 01/15/2025 15:02:11     
===============================================================================

===============================================================================
Candidate list
===============================================================================
Orig-Ip                                 Time Added
-------------------------------------------------------------------------------
192.0.2.2                               01/15/2025 15:02:11
192.0.2.3                               01/15/2025 15:02:13
-------------------------------------------------------------------------------
Number of Entries: 2
===============================================================================

===============================================================================
Pim Evpn Gateway
===============================================================================
DR Activation Timer Remaining: 0 secs                  
DR                           : Yes                     
DR Last Change               : 01/15/2025 15:02:11     
===============================================================================

===============================================================================
Candidate list
===============================================================================
Orig-Ip                                 Time Added
-------------------------------------------------------------------------------
192.0.2.2                               01/15/2025 15:02:11
192.0.2.3                               01/15/2025 15:02:13
-------------------------------------------------------------------------------
Number of Entries: 2
===============================================================================

[/]
A:admin@PE-3# show service id "SBD-8" evpn-mcast-gateway all

===============================================================================
Service Evpn Multicast Gateway
===============================================================================
Type                         : mvpn-pim                
Admin State                  : Enabled                 
DR Activation Timer          : 3 secs                  
Mvpn Evpn Gateway DR         : No                      
Pim  Evpn Gateway DR         : No                      
===============================================================================

===============================================================================
Mvpn Evpn Gateway
===============================================================================
DR Activation Timer Remaining: 0 secs                  
DR                           : No                      
DR Last Change               : 01/15/2025 15:02:47     
===============================================================================

===============================================================================
Candidate list
===============================================================================
Orig-Ip                                 Time Added
-------------------------------------------------------------------------------
192.0.2.2                               01/15/2025 15:02:47
192.0.2.3                               01/15/2025 15:02:47
-------------------------------------------------------------------------------
Number of Entries: 2
===============================================================================

===============================================================================
Pim Evpn Gateway
===============================================================================
DR Activation Timer Remaining: 0 secs                  
DR                           : No                      
DR Last Change               : 01/15/2025 15:02:47     
===============================================================================

===============================================================================
Candidate list
===============================================================================
Orig-Ip                                 Time Added
-------------------------------------------------------------------------------
192.0.2.2                               01/15/2025 15:02:47
192.0.2.3                               01/15/2025 15:02:47
-------------------------------------------------------------------------------
Number of Entries: 2
===============================================================================

The following cases are described in the following sections:

MEG/PEG non-DR does not attract traffic
MEG/PEG non-DR attracts traffic
MEG/PEG non-DR stops attracting traffic

MEG/PEG non-DR does not attract traffic

The MEG/PEG non-DR is initially configured such that it does not attract traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic none

When the MC receiver on PE-6 joins the MC group 225.0.0.1, PE-6 sends an EVPN-SMET BGP update message that is meant for SBD-8:

# On PE-6:
2 2025/01/15 15:10:11.813 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.6
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x4): IE:0/V3:1/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

The MEG/PEG DR and the MEG/PEG non-DR receive the EVPN-SMET BGP update message:

# On PE-2:
2 2025/01/15 15:10:12.455 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 90
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.6
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x4): IE:0/V3:1/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.6
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

# On PE-3:
2 2025/01/15 15:10:11.556 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 90
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.6
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x4): IE:0/V3:1/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.6
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
        "

The corresponding EVPN SMET routes to PE-6 at SBD-8 are valid and used in the MEG/PEG DR and in the MEG/PEG non-DR:

[/]
A:admin@PE-2# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete

===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

[/]
A:admin@PE-3# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

Only the MEG/PEG DR updates its MFIB at BD-8 with the entry based on the received EVPN-SMET BGP update message:

[/]
A:admin@PE-2# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
198.51.100.21   225.0.0.1             sbd-mpls:192.0.2.6:524274    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 1
===============================================================================

[/]
A:admin@PE-3# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Number of entries: 0
===============================================================================

Upon receiving the EVPN-SMET BGP update message from PE-6, only the MEG/PEG DR sends an MVPN-IPv4 Source-Join BGP update message that is meant for PE-8; the MEG/PEG non-DR does not.

# On PE-2:
4 2025/01/15 15:10:12.456 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
                                "

PE-8 receives the MVPN-IPv4 Source-Join BGP update message:

# On PE-8:
1 2025/01/15 15:10:11.940 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 90
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.2
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
        "

and uses the corresponding MVPN-IPv4 Source-Join route to the MEG/PEG DR:

[/]
A:admin@PE-8# show router bgp routes mvpn-ipv4 type source-join group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.8        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

PE-8 sends an MVPN-IPv4 Source-AD BGP update message that is meant for VPRN-1:

# On PE-8:
2 2025/01/15 15:10:11.941 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 72
    Flag: 0x90 Type: 14 Len: 29 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.8
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:64500:1
"

The MEG/PEG DR and the MEG/PEG non-DR receive the MVPN-IPv4 Source-AD BGP update message at VPRN-1:

# On PE-2:
7 2025/01/15 15:10:12.461 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 86
    Flag: 0x90 Type: 14 Len: 29 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.8
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.8
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:64500:1
"

# On PE-3:
5 2025/01/15 15:10:11.561 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 86
    Flag: 0x90 Type: 14 Len: 29 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.8
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.8
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:64500:1
        "

The corresponding MVPN-IPv4 Source-Ad routes to PE-8 are valid and used in the MEG/PEG DR and in the MEG/PEG non-DR:

[/]
A:admin@PE-2# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

[/]
A:admin@PE-3# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

Only the MEG/PEG DR creates PIM state at VPRN-1 with a non-empty outgoing interface list (OIL) and starts attracting traffic:

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  0
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

Because MLDP is used for I-PMSI, MC traffic is sent to all PEs in the same service. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-8 reaches the MEG/PEG DR and the MEG/PEG non-DR. The MEG/PEG DR forwards the MC traffic to PE-6: in the MEG/PEG DR, int-SBD-8 is in the OIL. In the MEG/PEG non-DR, int-SBD-8 is not in the OIL and the MEG/PEG non-DR does not forward the MC traffic:

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:02        
Up Time            : 0d 00:00:28        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:32
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-SBD-8
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 1702               Discarded Packets  : 0
Forwarded Octets   : 1664556            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:01        
Up Time            : 0d 00:00:29        Resolved By        : rtable-u
 
Up JP State        : Not Joined         Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : 
 
Curr Fwding Rate   : 0.000 kbps         
Forwarded Packets  : 0                  Discarded Packets  : 0
Forwarded Octets   : 0                  RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

PE-6 creates the MFIB at BD-4 with sbd-mpls:192.0.2.2:524270 toward the MEG/PEG DR:

[/]
A:admin@PE-6# show service id "BD-4" mfib

===============================================================================
Multicast FIB, Service 4
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sbd-mpls:192.0.2.2:524270    Local    Fwd
198.51.100.21   225.0.0.1             sap:1/1/c4/1:4               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 3
===============================================================================

The MEG/PEG DR forwards the MC traffic to PE-6 in the OISM EVPN network. On PE-6, int-SBD-8 is the incoming interface, while the local int-BD-4 to the MC receiver is in the OIL:

[/]
A:admin@PE-6# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 198.51.100.21
MRIB Src Flags     : direct             
Keepalive Timer    : Not Running        
Up Time            : 0d 00:01:48        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 198.51.100.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : int-BD-4
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 6601               Discarded Packets  : 0
Forwarded Octets   : 6455778            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

MEG/PEG non-DR attracts traffic

While MC traffic is being forwarded from the MC source on PE-8 to the MC receiver on PE-6, the MEG/PEG non-DR is reconfigured such that it attracts traffic from the MVPN network, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic from-pim-mvpn    # default

To allow the MEG/PEG non-DR to attract traffic, VPRN-1 on the MEG/PEG non-DR needs at least one non-SBD BD-9, as follows:

# On PE-3:
configure {
    service {
        vprn "VPRN-1" {
            admin-state enable
            ---snip---
            igmp {
                ---snip---
                interface "int-BD-9" { }
            }
            pim {
                ---snip---
                }
            }
            mvpn {
                ---snip---
            }
            bgp-ipvpn {
                mpls {
                    ---snip---
                    }
                }
            }
            ---snip---
            interface "int-BD-9" {
                ipv4 {
                    primary {
                        address 10.0.9.1
                        prefix-length 24
                    }
                }
                vpls "BD-9" { }
            }

# On PE-3:
configure {
    service {
        vpls "BD-9" {
            admin-state enable
            service-id 9
            customer "1"
            description "non-SBD_attached-VPRN-1"
            routed-vpls { }
            bgp 1 { }
            igmp-snooping {
                admin-state enable
            }
            bgp-evpn {
                evi 1000
                mpls 1 {
                    admin-state enable
                    auto-bind-tunnel {
                        resolution any
                    }
                }
            }

This reconfiguration has no immediate effect: changes to the MC traffic flow are applied only after the MC receiver rejoins the MC group. This is described in the following cases:

no receiver rejoin
enforced receiver rejoin

no receiver rejoin

PE-6 does not send a new EVPN-SMET BGP update message. So, the EVPN SMET routes and the MFIB at SBD-8 remain unchanged on the MEG/PEG DR and the MEG/PEG non-DR.

The MEG/PEG non-DR sends an MVPN-IPv4 Source-Join BGP update message too, indicating the MEG/PEG non-DR as next hop. The MVPN-IPv4 Source-Join BGP update message is meant for PE-8.

# On PE-3:
31 2025/01/15 15:13:58.981 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.3
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

The RR receives the MVPN-IPv4 Source-Join BGP update message and adds an additional MVPN-IPv4 Source-Join route for MC group 225.0.0.1 toward the MEG/PEG non-DR.

[/]
A:admin@RR-1# show router bgp routes mvpn-ipv4 type source-join
===============================================================================
 BGP Router ID:192.0.2.1        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
*>i   Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
*>i   Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.3                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 2
===============================================================================

Following section 11.1.3 of RFC 6514, the RD of the advertised MCAST-VPN NLRI is set to the RD of the VPN-IP route that contains the address carried in the Multicast Source field, when the local and the upstream PEs are in the same AS. Because the RDs for the two routes are the same, the RR does not forward the newly received MVPN-IPv4 Source-Join BGP update message, so PE-8 remains unaware of it.

Because PE-8 does not receive the MVPN-IPv4 Source-Join BGP update message from the MEG/PEG non-DR, PE-8 still has only one MVPN-IPv4 Source-Join route for MC group 225.0.0.1: toward the MEG/PEG DR.

Note: The exact behavior depends on the BGP configuration. In case of failure of the MEG/PEG DR, the RR advertises the route toward the MEG/PEG non-DR. If there would be a full mesh BGP network instead of a RR, PE-8 would receive the MVPN-IPv4 Source-Join BGP update message from the MEG/PEG non-DR and would add a second MVPN-IPv4 Source-Join route for MC group 225.0.0.1: toward the MEG/PEG non-DR. This route would be unused until the MEG/PEG DR would fail. add-path may be configured to advertise multiple copies of the same routes with different next hops.

Because PE-8 does not receive the MVPN-IPv4 Source-Join BGP update message from the MEG/PEG non-DR, PE-8 does not send a new MVPN-IPv4 Source-AD BGP update message. So, the MVPN-IPv4 Source-AD routes for MC group 225.0.0.1 remain unchanged on the MEG/PEG DR and the MEG/PEG non-DR.

Both the MEG/PEG DR and the MEG/PEG non-DR create PIM state at VPRN-1 with a non-empty OIL and start attracting traffic:

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

Because MLDP is used for I-PMSI, MC traffic is sent to all PEs in the same service. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-8 reaches the MEG/PEG DR and the MEG/PEG non-DR. The MEG/PEG DR forwards the MC traffic to PE-6: in the MEG/PEG DR, int-SBD-8 is in the OIL. The MEG/PEG non-DR forwards the MC traffic to PE-3: in the MEG/PEG non-DR, int-BD-9 is in the OIL.

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:02:39        
Up Time            : 0d 00:04:20        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:39
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-SBD-8
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 15917              Discarded Packets  : 0
Forwarded Octets   : 15566826           RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:02:55        
Up Time            : 0d 00:04:21        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:25
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-BD-9
 
Curr Fwding Rate   : 481.176 kbps       
Forwarded Packets  : 2092               Discarded Packets  : 0
Forwarded Octets   : 2045976            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

The MEG/PEG DR forwards the MC traffic to PE-6 in the OISM EVPN network. On PE-6, int-SBD-8 is the incoming interface, while the local int-BD-4 to the MC receiver is in the OIL:

[/]
A:admin@PE-6# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 198.51.100.21
MRIB Src Flags     : direct             
Keepalive Timer    : Not Running        
Up Time            : 0d 00:04:54        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 198.51.100.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : int-BD-4
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 17998              Discarded Packets  : 0
Forwarded Octets   : 17602044           RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

enforced receiver rejoin

With non-dr-attract-traffic from-pim-mvpn still applied, the MC receiver on PE-6 leaves the MC group 225.0.0.1.

PE-6 sends an EVPN-SMET unreachable NLRI BGP update message:

# On PE-6:
1 2025/01/15 15:16:10.141 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 37
    Flag: 0x90 Type: 15 Len: 33 Multiprotocol Unreachable NLRI:
        Address Family EVPN
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
"

The MEG/PEG DR and the MEG/PEG non-DR receive the EVPN-SMET unreachable NLRI BGP update message:

# On PE-2:
1 2025/01/15 15:16:10.783 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 37
    Flag: 0x90 Type: 15 Len: 33 Multiprotocol Unreachable NLRI:
        Address Family EVPN
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
"

# On PE-3:
1 2025/01/15 15:16:09.883 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 37
    Flag: 0x90 Type: 15 Len: 33 Multiprotocol Unreachable NLRI:
        Address Family EVPN
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
"

The MEG/PEG DR and the MEG/PEG non-DR send an MVPN-IPv4 Source-Join unreachable NLRI BGP update message:

# On PE-2:
4 2025/01/15 15:16:15.396 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 31
    Flag: 0x90 Type: 15 Len: 27 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
"

# On PE-3:
3 2025/01/15 15:16:13.070 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 31
    Flag: 0x90 Type: 15 Len: 27 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
"

PE-8 receives the MVPN-IPv4 Source-Join unreachable NLRI BGP update message:

# On PE-8:
1 2025/01/15 15:16:14.881 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 31
    Flag: 0x90 Type: 15 Len: 27 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
"

and sends an MVPN-IPv4 Source-AD unreachable NLRI BGP update message:

# On PE-8:
2 2025/01/15 15:16:14.881 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 27
    Flag: 0x90 Type: 15 Len: 23 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
"

the MEG/PEG DR and the MEG/PEG non-DR receive the MVPN-IPv4 Source-AD BGP update message at VPRN-1:

# On PE-2:
6 2025/01/15 15:16:15.401 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 27
    Flag: 0x90 Type: 15 Len: 23 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
"

# On PE-3:
5 2025/01/15 15:16:14.500 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 27
    Flag: 0x90 Type: 15 Len: 23 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
"

As a result, neither the MEG/PEG DR, nor the MEG/PEG non-DR have PIM state:

[/]
A:admin@PE-2# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
No Matching Entries
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
No Matching Entries
===============================================================================

After that, the MC receiver on PE-6 joins the MC group 225.0.0.1 again.

PE-6 sends a new EVPN-SMET BGP update message that is meant for SBD-8. So, the EVPN SMET routes and the MFIB at SBD-8 change accordingly on the MEG/PEG DR and on the MEG/PEG non-DR.

# On PE-6:
4 2025/01/15 15:16:53.864 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.6
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x4): IE:0/V3:1/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

[/]
A:admin@PE-2# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

[/]
A:admin@PE-3# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

[/]
A:admin@PE-2# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
198.51.100.21   225.0.0.1             sbd-mpls:192.0.2.6:524274    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 1
===============================================================================

[/]
A:admin@PE-3# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Number of entries: 0
===============================================================================

Both the MEG/PEG DR and the MEG/PEG non-DR send an MVPN-IPv4 Source-Join BGP update message that is meant for PE-8.

# On PE-2:
9 2025/01/15 15:16:54.506 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

# On PE-3:
7 2025/01/15 15:16:53.606 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.3
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

The RR receives the MVPN-IPv4 Source-Join BGP update messages and adds MVPN-IPv4 Source-Join routes for MC group 225.0.0.1 toward the MEG/PEG DR and toward the MEG/PEG non-DR.

[/]
A:admin@RR-1# show router bgp routes mvpn-ipv4 type source-join
===============================================================================
 BGP Router ID:192.0.2.1        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
*>i   Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
*>i   Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.3                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 2
===============================================================================

Because the RDs for the two routes are the same, the RR does forward only the MVPN-IPv4 Source-Join BGP update message from the MEG/PEG DR.

# On RR-1:
34 2025/01/15 15:16:54.852 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.8
"Peer 1: 192.0.2.8: UPDATE
Peer 1: 192.0.2.8 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 90
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.2
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

Because PE-8 receives only the MVPN-IPv4 Source-Join BGP update message from the MEG/PEG DR, PE-8 has only one MVPN-IPv4 Source-Join route for MC group 225.0.0.1: toward the MEG/PEG DR.

# On PE-8:
4 2025/01/15 15:16:53.991 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Received BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 90
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0x80 Type: 9 Len: 4 Originator ID: 192.0.2.2
    Flag: 0x80 Type: 10 Len: 4 Cluster ID:
        1.1.1.1
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

[/]
A:admin@PE-8# show router bgp routes mvpn-ipv4 type source-join group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.8        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

PE-8 sends an MVPN-IPv4 Source-AD BGP update message that is meant for VPRN-1.

# On PE-8:
5 2025/01/15 15:16:53.992 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 72
    Flag: 0x90 Type: 14 Len: 29 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.8
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:64500:1
"

So, the MVPN-IPV4 Source-AD routes for MC group 225.0.0.1 change accordingly on the MEG/PEG DR and on the MEG/PEG non-DR.

[/]
A:admin@PE-2# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

[/]
A:admin@PE-3# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

Both the MEG/PEG DR and the MEG/PEG non-DR create PIM state at VPRN-1 with a non-empty OIL and start attracting traffic:

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

Because MLDP is used for I-PMSI, MC traffic is sent to all PEs in the same service. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-8 reaches the MEG/PEG DR and the MEG/PEG non-DR. The MEG/PEG DR forwards the MC traffic to PE-6: in the MEG/PEG DR, int-SBD-8 is in the OIL. The MEG/PEG non-DR forwards the MC traffic to PE-3: in the MEG/PEG non-DR, int-BD-9 is in the OIL.

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:10        
Up Time            : 0d 00:00:19        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:40
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-SBD-8
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 1147               Discarded Packets  : 0
Forwarded Octets   : 1121766            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
admin@PE-3# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:09        
Up Time            : 0d 00:00:20        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:39
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-BD-9
 
Curr Fwding Rate   : 481.176 kbps       
Forwarded Packets  : 1257               Discarded Packets  : 0
Forwarded Octets   : 1229346            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

The MEG/PEG DR forwards the MC traffic to PE-6 in the OISM EVPN network. On PE-6, int-SBD-8 is the incoming interface, while the local int-BD-4 to the MC receiver is in the OIL:

[/]
A:admin@PE-6# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 198.51.100.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:01:48        
Up Time            : 0d 00:01:41        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : Join               Register Stop Exp  : 0d 00:00:00
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 198.51.100.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : int-BD-4
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 3662               Discarded Packets  : 0
Forwarded Octets   : 3581436            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

MEG/PEG non-DR stops attracting traffic

While MC traffic is being forwarded from the MC source on PE-8 to the MC receiver on PE-6, the MEG/PEG non-DR is reconfigured such that it stops attracting traffic from the MVPN network, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic none

This reconfiguration has no immediate effect: changes to the MC traffic flow are applied only after the MC receiver rejoins the MC group. This is described in the following cases:

no receiver rejoin
enforced receiver rejoin

no receiver rejoin

PE-6 does not send a new EVPN-SMET BGP update message. So, the EVPN SMET routes and the MFIB at SBD-8 remain unchanged on the MEG/PEG DR and the MEG/PEG non-DR.

Both the MEG/PEG DR and the MEG/PEG non-DR do not receive an EVPN-SMET BGP update message, so they do not send an MVPN-IPv4 Source-Join BGP update message. PE-8 does not receive an MVPN-IPv4 Source-Join BGP update message, so the MVPN-IPv4 Source-Join route for MC group 225.0.0.1 remains unchanged on PE-8.

PE-8 does not send an MVPN-IPv4 Source-AD BGP update message, so the MVPN-IPv4 Source-AD routes for MC group 225.0.0.1 remain unchanged on the MEG/PEG DR and the MEG/PEG non-DR.

Because MLDP is used for I-PMSI, MC traffic is sent to all PEs in the same service. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-8 reaches the MEG/PEG DR and the MEG/PEG non-DR. The MEG/PEG DR forwards the MC traffic to PE-6: in the MEG/PEG DR, int-SBD-8 is in the OIL. The MEG/PEG non-DR forwards the MC traffic to PE-3: in the MEG/PEG non-DR, int-BD-9 is in the OIL. The system keeps on behaving as before the reconfiguration.

enforced receiver rejoin

With non-dr-attract-traffic none still applied, the MC receiver on PE-6 leaves the MC group 225.0.0.1.

PE-6 sends an EVPN-SMET unreachable NLRI BGP update message.

The MEG/PEG DR and the MEG/PEG non-DR send an MVPN-IPv4 Source-Join unreachable NLRI BGP update message.

PE-8 sends an MVPN-IPv4 Source-AD unreachable NLRI BGP update message.

As a result, neither the MEG/PEG DR, nor the MEG/PEG non-DR have PIM state.

After that, the MC receiver on PE-6 joins the MC group 225.0.0.1 again.

PE-6 sends a new EVPN-SMET BGP update message that is meant for SBD-8. So, the EVPN SMET routes and the MFIB at SBD-8 change accordingly on the MEG/PEG DR and on the MEG/PEG non-DR.

# On PE-6:
4 2025/01/15 15:23:44.020 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.6
        Type: EVPN-SMET Len: 28 RD: 192.0.2.6:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 198.51.100.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 225.0.0.1, 
Orig Addr: 192.0.2.6/32, Flags(0x4): IE:0/V3:1/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

[/]
A:admin@PE-2# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

[/]
A:admin@PE-3# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
---snip---
u*>i  192.0.2.6:8         198.51.100.21
      0                   225.0.0.1
                          192.0.2.6
                          192.0.2.6

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

[/]
A:admin@PE-2# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
198.51.100.21   225.0.0.1             sbd-mpls:192.0.2.6:524274    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 1
===============================================================================

[/]
A:admin@PE-3# show service id "SBD-8" mfib

===============================================================================
Multicast FIB, Service 8
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Number of entries: 0
===============================================================================

The MEG/PEG DR sends an MVPN-IPv4 Source-Join BGP update message that is meant for PE-8. The MEG/PEG non-DR does not.

# On PE-2:
10 2025/01/15 15:23:44.663 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.2
        Type: Source-Join Len:22 RD: 192.0.2.8:1 SrcAS: 64500 
Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.8:2
"

Only PE-8, which has the MC source connected, reacts on the MVPN-IPv4 Source-Join BGP update message.

[/]
A:admin@PE-8# show router bgp routes mvpn-ipv4 type source-join group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.8        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

The additional MVPN-IPv4 Source-Join route for MC group 225.0.0.1 on PE-8 toward the MEG/PEG non-DR is no longer present.

[/]
A:admin@RR-1# show router bgp routes mvpn-ipv4 type source-join
===============================================================================
 BGP Router ID:192.0.2.1        AS:64500       Local AS:64500      
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete

===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
*>i   Source-Join                 -                      100         0
      192.0.2.8:1                 64500                  None        -
      192.0.2.2                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

PE-8 sends a new MVPN-IPv4 Source-AD BGP update message that is meant for VPRN-1. So, the MVPN-IPv4 Source-AD routes for MC group 225.0.0.1 change accordingly on the MEG/PEG DR and on the MEG/PEG non-DR.

# On PE-8:
6 2025/01/15 15:23:44.148 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 72
    Flag: 0x90 Type: 14 Len: 29 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.8
        Type: Source-AD Len: 18 RD: 192.0.2.8:1 Src: 198.51.100.21 Grp: 225.0.0.1
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:64500:1
"

[/]
A:admin@PE-2# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

[/]
A:admin@PE-3# show router bgp routes mvpn-ipv4 type source-ad group-ip 225.0.0.1
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Ad                   -                      100         0
      192.0.2.8:1                 -                      None        -
      192.0.2.8                   198.51.100.21                       
      No As-Path                  225.0.0.1                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  1
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
225.0.0.1                   (S,G)                        mpls-if-73731  0
   198.51.100.21                                                           
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-2# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:02:45        
Up Time            : 0d 00:00:45        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:15
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : int-SBD-8
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 2731               Discarded Packets  : 0
Forwarded Octets   : 2670918            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 225.0.0.1 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 192.0.2.8
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.8
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:02:43        
Up Time            : 0d 00:00:46        Resolved By        : rtable-u
 
Up JP State        : Not Joined         Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.8
Incoming Intf      : mpls-if-73731
Outgoing Intf List : 
 
Curr Fwding Rate   : 0.000 kbps         
Forwarded Packets  : 0                  Discarded Packets  : 0
Forwarded Octets   : 0                  RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

The MEG/PEG DR forwards the MC traffic to PE-6 in the OISM EVPN network. On PE-6, int-SBD-8 is the incoming interface, while the local int-BD-4 to the MC receiver is in the OIL:

[/]
A:admin@PE-6# show router "1" pim group detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 225.0.0.1
Source Address     : 198.51.100.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 198.51.100.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:01:36        
Up Time            : 0d 00:08:54        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : Join               Register Stop Exp  : 0d 00:00:00
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 198.51.100.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : int-BD-4
 
Curr Fwding Rate   : 477.264 kbps       
Forwarded Packets  : 21942              Discarded Packets  : 0
Forwarded Octets   : 21459276           RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

MC traffic from MC source on EVPN network to MC receiver on MVPN/PIM network

EVPN MC source - MVPN/PIM MC receiver example setup, with non-DR as UMH for PE-7 illustrates the MEG/PEG non-DR attract traffic function on MEG/PEG for OISM EVPN to MVPN/PIM interworking. This is the same setup as for the OISM EVPN to MVPN/PIM interworking (MEG/PEG function) with MLDP I-PMSI for OISM EVPN to MVPN/PIM interworking.

The MC source is connected to PE-5 in the EVPN network. The MC receiver is connected to PE-7 in the MVPN/PIM network. The MC source (10.0.3.21) sends MC traffic to the MC receiver (203.0.113.21) in MC group 239.0.0.4.

The following cases are described in the following sections:

MEG/PEG non-DR is upstream multicast hop
MEG/PEG DR is upstream multicast hop

MEG/PEG non-DR is upstream multicast hop

Figure 3. EVPN MC source - MVPN/PIM MC receiver example setup, with non-DR as UMH for PE-7

The upstream multicast hop (UMH) selection for PE-7 is configured to prefer PE-3 (MEG/PEG non-DR), as follows:

# On PE-7:
configure {
    service {
        vprn "VPRN-1" {
            mvpn {
                umh-selection highest-ip    # default

The following cases are described in the following sections:

MEG/PEG non-DR does not attract traffic
MEG/PEG non-DR attracts traffic
MEG/PEG non-DR stops attracting traffic

MEG/PEG non-DR does not attract traffic

The MEG/PEG non-DR is initially configured such that it does not attract traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic none

The MEG/PEG DR is configured with non-dr-attract-traffic from-pim-mvpn and generates a wildcard EVPN SMET route.

When the MC receiver on PE-7 joins the MC group 239.0.0.4, PE-7 sends an MVPN-IPv4 C-multicast Source-Join (S,G)=(10.0.3.21,239.0.0.4) BGP update message that is meant for PE-3 (UMH).

# On PE-7:
1 2025/01/15 15:34:15.348 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.7
        Type: Source-Join Len:22 RD: 192.0.2.3:1 SrcAS: 64500 
Src: 10.0.3.21 Grp: 239.0.0.4
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.3:2
"

Both the MEG/PEG DR and the MEG/PEG non-DR receive the MVPN-IPv4 C-multicast Source-Join BGP update message.

Only the MEG/PEG non-DR uses the corresponding MVPN-IPv4 Source-Join route to PE-7:

[/]
A:admin@PE-2# show router bgp routes mvpn-ipv4 type source-join group-ip 239.0.0.4
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
No Matching Entries Found.
===============================================================================

[/]
A:admin@PE-3# show router bgp routes mvpn-ipv4 type source-join group-ip 239.0.0.4
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Join                 -                      100         0
      192.0.2.3:1                 64500                  None        -
      192.0.2.7                   10.0.3.21                           
      No As-Path                  239.0.0.4                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

Only the MEG/PEG non-DR creates PIM state at VPRN-1 with a non-empty OIL and starts attracting traffic:

[/]
A:admin@PE-2# show router "1" pim group 239.0.0.4

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
239.0.0.4                   (S,G)                        int-SBD-8      0
   10.0.3.21                                                               
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 239.0.0.4

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
239.0.0.4                   (S,G)                        int-SBD-8      1
   10.0.3.21                                                               
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

Only the MEG/PEG non-DR sends an EVPN-SMET BGP update message that is meant for SBD-8:

# On PE-3:
4 2025/01/15 15:34:15.930 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.3
        Type: EVPN-SMET Len: 28 RD: 192.0.2.3:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 10.0.3.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 239.0.0.4, 
Orig Addr: 192.0.2.3/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

Upon receiving the EVPN-SMET BGP update message, PE-5 uses the corresponding EVPN SMET route to the MEG/PEG non-DR for the MC group 239.0.0.4:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.3:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.3
                          192.0.2.3

-------------------------------------------------------------------------------
Routes : 2
===============================================================================

and updates the MFIB at BD-3:

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
10.0.3.21       239.0.0.4             sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 3
===============================================================================

Because MLDP is used for I-PMSI, MC traffic is sent to every far-end that participates in that I-PMSI. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-5 reaches the MEG/PEG DR and the MEG/PEG non-DR. In the MEG/PEG DR, the MVPN tunnel is not in the OIL and the MEG/PEG DR does not forward the MC traffic. The MEG/PEG non-DR forwards the MC traffic to PE-7: in the MEG/PEG non-DR, the MVPN tunnel is in the OIL:

[/]
A:admin@PE-2# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 10.0.3.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:03:08        
Up Time            : 0d 00:00:32        Resolved By        : rtable-u
 
Up JP State        : Not Joined         Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : Join               Register Stop Exp  : 0d 00:00:00
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 10.0.3.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : 
 
Curr Fwding Rate   : 719.808 kbps       
Forwarded Packets  : 3014               Discarded Packets  : 0
Forwarded Octets   : 2947692            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 10.0.3.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:02:56        
Up Time            : 0d 00:00:34        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 10.0.3.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : mpls-if-73728
 
Curr Fwding Rate   : 719.808 kbps       
Forwarded Packets  : 3086               Discarded Packets  : 0
Forwarded Octets   : 3018108            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

PE-7 receives MC traffic via the MEG/PEG non-DR. On PE-7, the MVPN tunnel from the MEG/PEG non-DR is the incoming interface and the local to-receiver interface is in the OIL:

[/]
A:admin@PE-7# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 192.0.2.3
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.3
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:02        
Up Time            : 0d 00:00:27        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:32
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.3
Incoming Intf      : mpls-if-73730
Outgoing Intf List : to-receiver
 
Curr Fwding Rate   : 719.808 kbps       
Forwarded Packets  : 2449               Discarded Packets  : 0
Forwarded Octets   : 2395122            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

MEG/PEG non-DR attracts traffic

The MEG/PEG non-DR is reconfigured such that it attracts traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic from-evpn

This reconfiguration has immediate effect. The non-dr-attract-traffic from-evpn command causes the MEG/PEG non-DR to send a wildcard EVPN-SMET BGP update message that is meant for SBD-8:

# On PE-3:
7 2025/01/15 15:36:20.440 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 68
    Flag: 0x90 Type: 14 Len: 31 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.3
        Type: EVPN-SMET Len: 20 RD: 192.0.2.3:8, tag: 0, 
Mcast-Src-Len: 0, Mcast-Src-Addr: 0.0.0.0, 
Mcast-Grp-Len: 0, Mcast-Grp-Addr: 0.0.0.0, 
Orig Addr: 192.0.2.3/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

PE-5 receives the wildcard EVPN-SMET BGP update message and uses an additional wildcard EVPN SMET route to the MEG/PEG non-DR:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.3:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.3
                          192.0.2.3

u*>i  192.0.2.3:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.3
                          192.0.2.3

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

PE-5 updates the MFIB at BD-3:

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 2
===============================================================================

Because in the example setup the MC traffic for MC group 239.0.0.4 was already forwarded via the MEG/PEG non-DR, this does not introduce any change in the MC traffic flow, neither immediately upon reconfiguration, nor after a rejoin of the MC receiver on PE-7.

MEG/PEG non-DR stops attracting traffic

The MEG/PEG non-DR is reconfigured such that it stops attracting traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic none

This reconfiguration has immediate effect. The non-dr-attract-traffic none command causes the MEG/PEG non-DR to send a wildcard EVPN-SMET unreachable NLRI BGP update message:

# On PE-3:
2 2025/01/15 15:43:55.337 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 29
    Flag: 0x90 Type: 15 Len: 25 Multiprotocol Unreachable NLRI:
        Address Family EVPN
        Type: EVPN-SMET Len: 20 RD: 192.0.2.3:8, tag: 0, 
Mcast-Src-Len: 0, Mcast-Src-Addr: 0.0.0.0, 
Mcast-Grp-Len: 0, Mcast-Grp-Addr: 0.0.0.0, 
Orig Addr: 192.0.2.3/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
"

PE-5 receives the wildcard EVPN-SMET unreachable NLRI BGP update message and removes the wildcard EVPN SMET route to the MEG/PEG non-DR:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.3:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.3
                          192.0.2.3

-------------------------------------------------------------------------------
Routes : 2
===============================================================================

PE-5 updates the MFIB at BD-3:

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
10.0.3.21       239.0.0.4             sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 3
===============================================================================

MEG/PEG DR is upstream multicast hop

Figure 4. EVPN MC source - MVPN/PIM MC receiver example setup, with DR as UMH for PE-7

The upstream multicast hop selection for PE-7 is reconfigured to prefer PE-2 (MEG/PEG DR), as follows:

# On PE-7:
configure {
    service {
        vprn "VPRN-1" {
            mvpn {
                umh-selection unicast-rt-pref

PE-7 sends an MVPN-IPv4 C-multicast Source-join unreachable NLRI BGP update message and an MVPN-IPv4 C-multicast Source-join (S,G)=(10.0.3.21,239.0.0.4) BGP update message that is meant for the MEG/PEG DR (UMH):

# On PE-7:
1 2025/01/15 15:46:17.351 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 31
    Flag: 0x90 Type: 15 Len: 27 Multiprotocol Unreachable NLRI:
        Address Family MVPN_IPV4
        Type: Source-Join Len:22 RD: 192.0.2.3:1 SrcAS: 64500 
Src: 10.0.3.21 Grp: 239.0.0.4
"
---snip---
8 2025/01/15 15:54:57.732 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 33 Multiprotocol Reachable NLRI:
        Address Family MVPN_IPV4
        NextHop len 4 NextHop 192.0.2.7
        Type: Source-Join Len:22 RD: 192.0.2.2:1 SrcAS: 64500 
Src: 10.0.3.21 Grp: 239.0.0.4
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x80 Type: 4 Len: 4 MED: 0
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 8 Len: 4 Community:
        no-export
    Flag: 0xc0 Type: 16 Len: 8 Extended Community:
        target:192.0.2.2:2
"

Both the MEG/PEG DR and the MEG/PEG non-DR receive the MVPN-IPv4 C-multicast Source-Join BGP update message.

Only the MEG/PEG DR uses an MVPN-IPv4 Source-Join route to PE-7:

[/]
A:admin@PE-2# show router bgp routes mvpn-ipv4 type source-join group-ip 239.0.0.4
===============================================================================
 BGP Router ID:192.0.2.2        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
u*>i  Source-Join                 -                      100         0
      192.0.2.2:1                 64500                  None        -
      192.0.2.7                   10.0.3.21                           
      No As-Path                  239.0.0.4                           
-------------------------------------------------------------------------------
Routes : 1
===============================================================================

[/]
A:admin@PE-3# show router bgp routes mvpn-ipv4 type source-join group-ip 239.0.0.4
===============================================================================
 BGP Router ID:192.0.2.3        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
      RD                          SourceAS               Path-Id     IGP Cost
      Nexthop                     SourceIP                           Label
      As-Path                     GroupIP                            
-------------------------------------------------------------------------------
No Matching Entries Found.
===============================================================================

Only the MEG/PEG DR creates PIM state at VPRN-1 with a non-empty OIL and starts attracting traffic:

[/]
A:admin@PE-2# show router "1" pim group 239.0.0.4

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
239.0.0.4                   (S,G)                        int-SBD-8      1
   10.0.3.21                                                               
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 239.0.0.4

===============================================================================
Legend:  A = Active   S = Standby
===============================================================================
PIM Groups ipv4
===============================================================================
Group Address               Type                Spt Bit  Inc Intf       No.Oifs
   Source Address              RP                  State    Inc Intf(S) 
-------------------------------------------------------------------------------
239.0.0.4                   (S,G)                        int-SBD-8      0
   10.0.3.21                                                               
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

Only the MEG/PEG DR sends an EVPN-SMET BGP update message that is meant for SBD-8:

# On PE-2:
8 2025/01/15 15:54:59.214 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 76
    Flag: 0x90 Type: 14 Len: 39 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.2
        Type: EVPN-SMET Len: 28 RD: 192.0.2.2:8, tag: 0, 
Mcast-Src-Len: 32, Mcast-Src-Addr: 10.0.3.21, 
Mcast-Grp-Len: 32, Mcast-Grp-Addr: 239.0.0.4, 
Orig Addr: 192.0.2.2/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

Upon receiving the EVPN-SMET BGP update message, PE-5 uses the corresponding EVPN SMET route to the MEG/PEG DR for the MC group 239.0.0.4:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.2:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.2
                          192.0.2.2

-------------------------------------------------------------------------------
Routes : 2
===============================================================================

and updates the MFIB at BD-3. PE-5 ignores any (S,G) or (*,G) EVPN SMET route from a PE when it receives a (*,*) wildcard EVPN SMET route from the same PE. So, PE-5 ignores the group-specific EVPN SMET route from the MEG/PEG DR.

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 2
===============================================================================

Because MLDP is used for I-PMSI, MC traffic is sent to every far-end that participates in that I-PMSI. Nodes that do not have MC state or connected MC receivers drop the MC traffic that they receive. So, MC traffic from the MC source on PE-5 reaches the MEG/PEG DR and the MEG/PEG non-DR. The MEG/PEG DR forwards the MC traffic to PE-7: the MVPN tunnel is in the OIL. In the MEG/PEG non-DR, the MVPN tunnel is not in the OIL and the MEG/PEG non-DR does not forward the MC traffic.

[/]
A:admin@PE-2# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 10.0.3.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:02:15        
Up Time            : 0d 00:21:14        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : Join               Register Stop Exp  : 0d 00:00:00
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 10.0.3.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : mpls-if-73728
 
Curr Fwding Rate   : 715.896 kbps       
Forwarded Packets  : 117076             Discarded Packets  : 0
Forwarded Octets   : 114500328          RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

[/]
A:admin@PE-3# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 10.0.3.21
MRIB Src Flags     : direct             
Keepalive Timer Exp: 0d 00:03:07        
Up Time            : 0d 00:21:15        Resolved By        : rtable-u
 
Up JP State        : Not Joined         Up JP Expiry       : 0d 00:00:00
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 10.0.3.21
Incoming Intf      : int-SBD-8
Outgoing Intf List : 
 
Curr Fwding Rate   : 715.896 kbps       
Forwarded Packets  : 117240             Discarded Packets  : 0
Forwarded Octets   : 114660720          RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

PE-7 receives MC traffic via the MEG/PEG DR. On PE-7, the MVPN tunnel from the MEG/PEG DR is the incoming interface and the local to-receiver interface is in the OIL:

[/]
A:admin@PE-7# show router "1" pim group 239.0.0.4 detail

===============================================================================
PIM Source Group ipv4
===============================================================================
Group Address      : 239.0.0.4
Source Address     : 10.0.3.21
RP Address         : 0
Advt Router        : 192.0.2.2
Flags              :                    Type               : (S,G)
Mode               : sparse             
MRIB Next Hop      : 192.0.2.2
MRIB Src Flags     : remote             
Keepalive Timer Exp: 0d 00:03:04        
Up Time            : 0d 00:00:26        Resolved By        : rtable-u
 
Up JP State        : Joined             Up JP Expiry       : 0d 00:00:34
Up JP Rpt          : Not Joined StarG   Up JP Rpt Override : 0d 00:00:00
 
Register State     : No Info            
Reg From Anycast RP: No                 
 
Rpf Neighbor       : 192.0.2.2
Incoming Intf      : mpls-if-73733
Outgoing Intf List : to-receiver
 
Curr Fwding Rate   : 715.896 kbps       
Forwarded Packets  : 2412               Discarded Packets  : 0
Forwarded Octets   : 2358936            RPF Mismatches     : 0
Spt threshold      : 0 kbps             ECMP opt threshold : 7
Admin bandwidth    : 1 kbps             
-------------------------------------------------------------------------------
Groups : 1
===============================================================================

The following cases are described in the following sections:

MEG/PEG non-DR attracts traffic
MEG/PEG non-DR stops attracting traffic

MEG/PEG non-DR attracts traffic

The MEG/PEG non-DR is reconfigured such that it attracts traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic from-evpn

This reconfiguration has immediate effect. The non-dr-attract-traffic from-evpn command causes the MEG/PEG non-DR to send a wildcard EVPN-SMET BGP update message that is meant for SBD-8:

# On PE-3:
7 2025/01/15 15:57:03.540 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 68
    Flag: 0x90 Type: 14 Len: 31 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.3
        Type: EVPN-SMET Len: 20 RD: 192.0.2.3:8, tag: 0, 
Mcast-Src-Len: 0, Mcast-Src-Addr: 0.0.0.0, 
Mcast-Grp-Len: 0, Mcast-Grp-Addr: 0.0.0.0, 
Orig Addr: 192.0.2.3/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        target:64500:8
        bgp-tunnel-encap:MPLS
"

PE-5 receives the wildcard EVPN-SMET BGP update message and uses an additional wildcard EVPN SMET route to the MEG/PEG non-DR:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.2:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.3:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.3
                          192.0.2.3

-------------------------------------------------------------------------------
Routes : 3
===============================================================================

PE-5 updates the MFIB at BD-3:

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
                                      sbd-mpls:192.0.2.3:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 2
===============================================================================

Because in the example setup the MC traffic for MC group 239.0.0.4 was already forwarded via the MEG/PEG DR, this does not introduce any change in the MC traffic flow, neither immediately upon reconfiguration, nor after a rejoin of the MC receiver on PE-7.

MEG/PEG non-DR stops attracting traffic

The MEG/PEG non-DR is reconfigured such that it stops attracting traffic, as follows:

# On PE-3:
configure {
    service {
        vpls "SBD-8" {
            routed-vpls {
                multicast {
                    evpn-gateway {
                        admin-state enable
                        non-dr-attract-traffic none

This reconfiguration has immediate effect. The non-dr-attract-traffic none command causes the MEG/PEG non-DR to send a wildcard EVPN-SMET unreachable NLRI BGP update message:

# On PE-3:
2 2025/01/15 16:02:45.376 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 29
    Flag: 0x90 Type: 15 Len: 25 Multiprotocol Unreachable NLRI:
        Address Family EVPN
        Type: EVPN-SMET Len: 20 RD: 192.0.2.3:8, tag: 0, 
Mcast-Src-Len: 0, Mcast-Src-Addr: 0.0.0.0, 
Mcast-Grp-Len: 0, Mcast-Grp-Addr: 0.0.0.0, 
Orig Addr: 192.0.2.3/32, Flags(0x0): IE:0/V3:0/V2:0/V1:0 
"

PE-5 receives the wildcard EVPN-SMET unreachable NLRI BGP update message and removes the wildcard EVPN SMET route to the MEG/PEG non-DR:

[/]
A:admin@PE-5# show router bgp routes evpn smet
===============================================================================
 BGP Router ID:192.0.2.5        AS:64500       Local AS:64500      
===============================================================================
---snip---
===============================================================================
BGP EVPN Smet Routes
===============================================================================
Flag  Route Dist.         Src Address
      Tag                 Grp Address
                          Orig Address
                          NextHop
-------------------------------------------------------------------------------
u*>i  192.0.2.2:8         0.0.0.0
      0                   0.0.0.0
                          192.0.2.2
                          192.0.2.2

u*>i  192.0.2.2:8         10.0.3.21
      0                   239.0.0.4
                          192.0.2.2
                          192.0.2.2

-------------------------------------------------------------------------------
Routes : 2
===============================================================================

PE-5 updates the MFIB at BD-3:

[/]
A:admin@PE-5# show service id "BD-3" mfib

===============================================================================
Multicast FIB, Service 3
===============================================================================
Source Address  Group Address         Port Id                      Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     sap:1/1/c4/1:3               Local    Fwd
                                      sbd-mpls:192.0.2.2:524270    Local    Fwd
*               * (mac)               sbd-mpls:192.0.2.2:524270    Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 2
===============================================================================

Conclusion

SR OS supports MEG/PEG non-DR attract traffic in the interworking of OISM EVPN networks and OISM MVPN/PIM networks in both directions.