Port-level egress rate limiting

This chapter provides information to configure the port-level egress-rate command using the CLI.

Overview

Egress port rate limiting allows the device to limit the traffic that egresses through a port to a value less than the available link bandwidth.

This feature is useful when connecting the 7210 SAS to an Ethernet-over-SDH (EoSDH) or microwave network, where the network allocates predetermined bandwidth to the nodes connecting to it, based on the transport bandwidth requirement. When connecting to such a network, it is important that the traffic sent into the SDH node does not exceed the configured values, because the SDH network does not have the QoS capabilities and buffers required to prioritize the ingress traffic.

Egress rate attributes include the following:

  • Per-port configuration of the maximum egress port rate is allowed, using the egress-rate CLI command.

  • Ethernet ports configured as access and access-uplink support this feature.

  • The port scheduler distributes the available maximum egress bandwidth based on the CIR/PIR configuration parameters provisioned for the queues.

  • The burst parameter is not user-configurable and is set to a default by software.

  • When ports are members of a LAG, all the ports use the same value for the egress-rate and the max-burst parameters.

  • If frame overhead accounting (also known as frame-based accounting) is enabled, the queue scheduler accounts for the Ethernet frame overhead.

  • When an egress-rate sub-rate value is provided, the access-uplink port egress queue rates that are specified using percentages will use the egress-rate value instead of the port bandwidth to configure the appropriate queue rates if the egress rate is less than the port bandwidth. Configuration of egress port rate to different values will result in a corresponding dynamic adjustment of rates for the egress queues configured on access-uplink ports.

  • On the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C, when an egress-rate sub-rate value is provided, the network or hybrid port egress queue rates that are specified using percentages use the egress-rate value instead of the port bandwidth to configure the queue rates if the egress rate is less than the port bandwidth. Manually configuring the egress port rate to different values results in a corresponding dynamic adjustment of rates for the egress queues that are configured on the network ports.

    For hybrid ports, port queue rates specified as a percentage in the QoS policy change based on the lowest values of nw-egr-agg-shaper-rate, egress-rate, or the port bandwidth.

  • When the egress-rate sub-rate value is set, CBS/MBS of the associated network queues is not modified automatically. The user has an option to change the CBS/MBS values if necessary.

Basic configurations

For port-level rate limiting, the following considerations apply:

  • The egress-rate command is in the config>port>ethernet context.

  • The egress-rate command configures the maximum rate (in kb/s).

By default, the egress-rate command is not set on the port, and the port operates at the maximum line-rate speed it is operating at.

The following is a sample configuration output that shows the egress-rate configuration for a port.

*A:Dut-1>config>port# info 
----------------------------------------------
        ethernet
            egress-rate 120000
        exit
        no shutdown
----------------------------------------------
*A:Dut-1>config>port#

Modifying the port-level egress-rate command

To modify egress rate parameters, apply an egress-rate command with new egress-rate values.

Removing the port-level egress-rate command

To remove the egress-rate command from a port, use the no option with the egress-rate command. Do not include the rate for the egress-rate and max-burst options.

Use the following syntax to remove the egress-rate command from a port.

config>port>ethernet# no egress-rate

The following is a sample configuration output that shows the removal of the egress-rate configuration from a port.

*A:Dut-1>config>port# no ethernet egress-rate
*A:Dut-1>config>port# info 
----------------------------------------------
        ethernet
        exit
        no shutdown
----------------------------------------------
*A:Dut-1>config>port#

Port level egress-rate command reference

Command descriptions

Configuration commands

egress-rate
Syntax

egress-rate sub-rate

no egress-rate

Context

config>port>ethernet

Platforms

Supported on all 7210 SAS platforms as described in this document

Description

This command configures maximum egress rate for a port. The egress-rate is configured as kb/s.

The no form of this command removes egress-rate from the port.

Parameters
sub-rate

Specifies an integer value between 1 and 1000000 kb/s.

Show commands

port
Syntax

port [port-id]

Context

show

Platforms

Supported on all 7210 SAS platforms as described in this document

Description

This command displays egress rate and max burst value set for the port as well as other port details.

Parameters
port-id

Displays information about the specific port ID.

Output

The following output is an example of port information, and Output fields: port describes the output fields.

Sample output
*A:dut-1>config>qos>network-queue# show port 1/1/1 
===============================================================================
Ethernet Interface
===============================================================================
Description        : 10/100/Gig Ethernet SFP
Interface          : 1/1/1                      Oper Speed       : 1 Gbps      
Link-level         : Ethernet                   Config Speed     : 1 Gbps      
Admin State        : up                         Oper Duplex      : full        
Oper State         : up                         Config Duplex    : full        
Physical Link      : Yes                        MTU              : 1514        
IfIndex            : 35684352                   Hold time up     : 0 seconds   
Last State Change  : 01/17/2011 04:05:37        Hold time down   : 0 seconds   
Last Cleared Time  : N/A                                                       

Configured Mode    : access                     Encap Type       : null        
Dot1Q Ethertype    : 0x8100                     QinQ Ethertype   : 0x8100      
Net. Egr. Queue Pol: default                    Access Egr. Qos *: 1           
Egr. Sched. Pol    : default                    Network Qos Pol  : n/a         
Auto-negotiate     : limited                    MDI/MDX          : MDI         
Accounting Policy  : None                       Collect-stats    : Disabled    
Egress Rate        : Default                    Max Burst        : Default     
Uplink             : No                                                        
                                      
Down-when-looped   : Disabled                   Keep-alive       : 10          
Loop Detected      : False                      Retry            : 120         

Configured Address : 00:78:76:45:54:02
Hardware Address   : 00:78:76:45:54:02
Cfg Alarm          :                                                   
Alarm Status       :                                                   

Transceiver Data

Transceiver Type   : SFP                                                      
Model Number       : 3HE00027AAAA02  ALA  IPUIAELDAB=                         
TX Laser Wavelength: 850 nm                     Diag Capable     : yes         
Connector Code     : LC                         Vendor OUI       : 00:0a:1d    
Manufacture date   : 2008/08/10                 Media            : Ethernet    
Serial Number      : OPCPCH08052638                                           
Part Number        : TRPAG1SXLAES-TM                                          
Optical Compliance : GIGE-SX                                                  
Link Length support: 550m for 50u MMF; 280m for 62.5u MMF;                    
===============================================================================
Traffic Statistics
===============================================================================
                                                   Input                 Output
-------------------------------------------------------------------------------
Octets                                                 0                      0
Packets                                                0                      0
Errors                                                 0                      0
===============================================================================
* indicates that the corresponding row element may have been truncated.
===============================================================================
Port Statistics
===============================================================================
                                                   Input                 Output
-------------------------------------------------------------------------------
Unicast Packets                                        0                      0
Multicast Packets                                      0                      0
Broadcast Packets                                      0                      0
Discards                                               0                      0
Unknown Proto Discards                                 0                       
===============================================================================
===============================================================================
Ethernet-like Medium Statistics
===============================================================================
Alignment Errors :                   0  Sngl Collisions  :                   0 
FCS Errors       :                   0  Mult Collisions  :                   0 
SQE Test Errors  :                   0  Late Collisions  :                   0 
CSE              :                   0  Excess Collisns  :                   0 
Too long Frames  :                   0  Int MAC Tx Errs  :                   0 
Symbol Errors    :                   0  Int MAC Rx Errs  :                   0 
================================================================ 
*A:dut-1>config>qos>network-queue#

Table 1. Output fields: port

Label

Description

Ethernet Interface

Description

A text description of the port

Interface

The port ID displayed in the slot/mda/port format

Oper Speed

The operating speed of the interface

Link-level

Ethernet — The port is configured as Ethernet

Config Speed

The configured speed of the interface

Admin State

up — The port is administratively up

down — The port is administratively down

Oper Duplex

The operating duplex mode of the interface

Oper State

up — The port is operationally up

down — The port is operationally down

Config Duplex

full — The link is configured to full-duplex mode

half — The link is configured to half-duplex mode

Physical Link

Yes — A physical link is present

No — A physical link is not present

MTU

The size of the largest packet that can be sent/received on the Ethernet physical interface, specified in octets

IfIndex

The interface’s index number, which reflects its initialization sequence

Hold time up

The link-up dampening time in seconds. The port link dampening timer value that reduces the number of link transitions reported to upper layer protocols.

Last State Change

The last time that the operational status of the port changed state

Hold time down

The link-down dampening time in seconds. The down timer controls the dampening timer for link down transitions.

Last Cleared Time

The time since the last clear

Configured Mode

network — The port is configured for transport network use

access — The port is configured for service access

hybrid — The port is configured for hybrid use (transport network and service access per VLAN)

Encap Type

null — Ingress frames do not use any tags or labels to delineate a service

dot1q — Ingress frames carry 802.1Q tags, where each tag signifies a different service

qinq — Ingress frames carry two 802.1Q tags, where the outer tag is the service provider tag and the inner tag is the customer service tag

Dot1Q Ethertype

The protocol carried in a dot1q Ethernet frame

QinQ Ethertype

The protocol carried in a QinQ Ethernet frame

Net.Egr. Queue Pol.

The number of the associated network egress queue QoS policy, or default if the default policy is used

Access Egr. QoS

Specifies the access egress policy or that the default policy 1 is in use

Egr. Sched. Pol

Specifies the port scheduler policy or that the default policy default is in use

Network Qos Pol

The QoS policy ID applied to the port

Auto-negotiate

true — The link attempts to automatically negotiate the link speed and duplex parameters

false — The duplex and speed values are used for the link

MDI/MDX

Indicates the Ethernet interface type

Accounting Policy

The accounting policy applied to the port

Collect-stats

Enabled — The collection of accounting and statistical data for the network Ethernet port is enabled

When applying accounting policies, the data by default will be collected in the appropriate records and written to the designated billing file.

Disabled — Collection is disabled

Statistics are still accumulated by the IOM cards, however, the CPU will not obtain the results and write them to the billing file.

Egress Rate

The maximum amount of egress bandwidth (in kilobits per second) that this Ethernet interface can generate

Down-when-looped

Enabled — The down-when-looped feature is enabled on the port

Disabled — The down-when-looped feature is disabled on the port

Keep-alive

The time interval between keepalive PDUs transmitted toward the network during loop detection by the down-when-looped feature

Loop Detected

Indicates whether a loop is detected on the port

Retry

The minimum wait time before the port is re-enabled after it is brought down as a result of a loop detection

Configured Address

The base chassis Ethernet MAC address

Hardware Address

The interface hardware-assigned or system-assigned MAC address at its protocol sublayer

Cfg Alarm

The type of alarms to be logged and reported for the port

Alarm Status

The current alarm state

Transceiver Data

Transceiver Type

The installed transceiver type

Model Number

The model number of the installed transceiver

TX Laser Wavelength

The wavelength of the transmission laser

Diag Capable

Displays whether digital diagnostic monitoring (DDM) is capable for the transceiver

Connector Code

The transceiver connector code

Vendor OUI

The vendor organizationally unique identifier (OUI)

Manufacture Date

The manufacture date of the transceiver

Media

The intended media for the transceiver to send and receive

Serial Number

The serial number of the transceiver

Part Number

The part number of the transceiver

Optical Compliance

The optical compliance code of the transceiver

Link Length Support

The supported link length of the transceiver

Traffic Statistics

Octets input/output

The total number of octets received and transmitted on the port

Packets input/output

The number of packets, delivered by this sublayer to a higher (sub) layer, which were not addressed to a multicast or broadcast address at this sublayer. The total number of packets that higher-level protocols requested be transmitted, and which were not addressed to a multicast or broadcast address at this sublayer, including those that were discarded or not sent.

Errors Input/Output

For packet-oriented interfaces, the number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol. For character-oriented or fixed-length interfaces, the number of inbound transmission units that contained errors preventing them from being deliverable to a higher-layer protocol.

For packet-oriented interfaces, the number of outbound packets that could not be transmitted because of errors. For character-oriented or fixed-length interfaces, the number of outbound transmission units that could not be transmitted because of errors.

Port Statistics

Unicast Packets Input/Output

The number of packets, delivered by this sublayer to a higher (sub) layer, which were not addressed to a multicast or broadcast address at this sublayer. The total number of packets that higher-level protocols requested be transmitted, and which were not addressed to a multicast or broadcast address at this sublayer, including those that were discarded or not sent.

Multicast Packets Input/Output

The number of packets, delivered by this sublayer to a higher (sub) layer, which were not addressed to a unicast or broadcast address at this sublayer. The total number of packets that higher-level protocols requested be transmitted, and which were not addressed to a unicast or broadcast address at this sublayer, including those that were discarded or not sent

Broadcast Packets Input/Output

The number of packets, delivered by this sublayer to a higher (sub) layer, which were not addressed to a unicast or multicast address at this sublayer. The total number of packets that higher-level protocols requested be transmitted, and which were not addressed to a unicast or multicast address at this sublayer, including those that were discarded or not sent.

Discards Input/Output

The number of inbound/outbound packets chosen to be discarded to possibly free up buffer space

Unknown Proto Discards Input/Output

For packet-oriented interfaces, the number of packets received via the interface that were discarded because of an unknown or unsupported protocol. For character-oriented or fixed-length interfaces that support protocol multiplexing, the number of transmission units received via the interface that were discarded because of an unknown or unsupported protocol. For any interface that does not support protocol multiplexing, this counter will always be 0. Unknown proto discards do not show up in the packet counts

Ethernet-like Medium Statistics

Alignment Errors

The total number of packets received that had a length (excluding framing bits, but including FCS octets) of between 64 and 1518 octets, inclusive, but that had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a non-integral number of octets

Sngl Collisions

The number of frames that are involved in a single collision, and are subsequently transmitted successfully

FCS Errors

The number of frames received that are an integral number of octets in length but do not pass the FCS check

Mult Collisions

The number of frames that are involved in more than one collision and are subsequently transmitted successfully

SQE Test Errors

The number of times that the SQE TEST ERROR is received

Late Collisions

The number of times that a collision is detected later than one slotTime into the transmission of a packet

CSE

The number of times that the carrier sense condition was lost or never asserted when attempting to transmit a frame

Excess Collisns

The number of frames for which a transmission fails as a result of excessive collisions

Too long Frames

The number of frames received that exceed the maximum permitted frame size

Int MAC Tx Errs

The number of frames for which a transmission fails as a result of an internal MAC sublayer transmit error

Symbol Errors

For an interface operating at 100 Mb/s, the number of times there was an invalid data symbol when a valid carrier was present

Int MAC Rx Errs

The number of frames for which a reception fails as a result of an internal MAC sublayer receive error