BNG-UP health reporting

The BNG-UP can send health reports to the MAG-c using PFCP Node Report messages. The MAG-c uses the health reports to determine the need for a BNG-UP status change (active or standby). Per FSG, the MAG-c selects the active and the standby BNG-UP. For example, the MAG-c can base its decision on link failures in the access network.

The BNG-UP supports health reports for the following contexts:

per network instance
Use the commands in the following context to configure the health monitoring for the applicable service.
```
configure service ies subscriber-mgmt up-resiliency
configure service vprn subscriber-mgmt up-resiliency
```
The health reports per network instance can, for example, be used to indicate the status of the network where the subscriber is serviced.
per Layer 2 access ID
Use the commands in the following context to configure health monitoring.
```
configure service vpls capture-sap pfcp up-resiliency
```
The health reports per Layer 2 access ID can, for example, be used to indicate the status of the access links.

Each health report generates a health value between 0 (unhealthy) and 100 (healthy). The base health value is 100 and decreases with the number of failed members in the operation group x the configured health drop number for the operational group.

Whenever a member of the operational group changes its state (fails or recovers), the BNG-UP calculates the health value and sends an updated report to the MAG-c.

To configure the operational group and the health drop number, use the monitor-oper-group and the monitor-oper-group health-drop commands in the previously mentioned contexts.

For more information about operational groups, see 7450 ESS, 7750 SR, 7950 XRS, and VSR Layer 3 Services Guide: IES and VPRN, sections Object grouping and state monitoring.

With the following example configuration, the BNG-UP sends health reports for Layer 2 access ID (port) lag-access. The operational group has five members (port 1/1/20 to port 1/1/24) and the health value decreases with 51 per failed member, that is, with 20% of the base health value.

Configuration of health reports for Layer 2 access ID (port) lag-access

[ex:/configure port 1/1/20]
A:admin@BNG-UPF# info
    oper-group "lag_access_health"
[ex:/configure port 1/1/21]
A:admin@BNG-UPF# info
    oper-group "lag_access_health"
[ex:/configure port 1/1/22]
A:admin@BNG-UPF# info
    oper-group "lag_access_health"
[ex:/configure port 1/1/23]
A:admin@BNG-UPF# info
    oper-group "lag_access_health"
[ex:/configure port 1/1/24]
A:admin@BNG-UPF# info
    oper-group "lag_access_health"
[ex:/configure service vpls "access" capture-sap lag-access:*.* pfcp up-resiliency]
A:admin@BNG-UPF# info
    monitor-oper-group "lag_access_health" {
        health-drop 20
    }

The BNG-UP sends a health report for every status change in the operational group. Additionally, it sends all health reports periodically (every 60 seconds) and when a PFCP audit is requested.

With the following example configuration, the BNG-UP sends health reports for network instance HSI. The health drop number is not configured, that is, the default value of 100 is used. The health is based on a BFD session that is used to check if the BNG-UP is isolated from the rest of the network. When the BFD session is up, the health value equals 100, otherwise, the health value equals 0.

Configuration of health reports for network instance HSI

[ex:/configure service oper-group "hsi-bfd"]
A:admin@BNG-UPF# info
    bfd-liveness {
        router-instance "to_uplink_router"
        interface-name "endpoint"
        dest-ip 203.0.113.10
    }
[ex:/configure service vprn "hsi" subscriber-mgmt up-resiliency]
A:admin@BNG-UPF# info
    monitor-oper-group "hsi-bfd" {
    }