13. QoS port scheduler policies for 7210 SAS-T

This section provides information to configure port scheduler policies using the command line interface.

13.1. Overview

This section provides an overview of QoS port scheduler policies on the 7210 SAS-T.

13.1.1. Configuring port scheduler policies

The port-scheduler-policy command creates a port scheduler template which may be assigned to an egress port. Only one port scheduler policy is allowed per port. There is a “default” port-scheduler policy (which services the queues of the port in a Strict order) associated with each port. To change the behavior, users can associate the port with another port-scheduler policy. The policy contains mode commands to set the mode of scheduling (RR, Strict, WRR, WDRR) and queue commands to set the weight of the queue, when the mode is set to one of WRR and WDRR. In WRR/WDRR, a strict option treats that particular queue as a strict queue, this leads to a hybrid mode of scheduling (WRR+Strict, WDRR+Strict).

13.1.2. Basic configurations

A basic QoS port scheduler policy must conform to the following:

  1. Each QoS port scheduler policy must have a unique policy name.

13.1.2.1. Creating a QoS port scheduler policy

To create a port scheduler policy, define the following:

  1. a port scheduler policy name
  2. include a description - provides a brief overview of policy features

Use the following syntax to create a QoS port scheduler policy.

Note that the create keyword is included in the command syntax upon creation of a policy.

CLI Syntax:
config>qos
port-scheduler-policy port-scheduler-name [create]
description description-string
mode {strict | rr | wrr | wdrr}
queue queue-id [strict | weight weight]

The following is a sample port scheduler policy configuration output.

*A:card-1>config>qos>port-sched-plcy# info
----------------------------------------------
            mode WRR
            queue 1 weight 1
            queue 2 weight 3
            queue 3 weight 5
            queue 5 weight 5
            queue 6 weight 1
----------------------------------------------
*A:card-1>config>qos>port-sched-plcy#

13.2. Service management tasks

This section describes the service management tasks.

13.2.1. Copying and Overwriting scheduler policies

You can copy an existing QoS policy, rename it with a new QoS policy value, or overwrite an existing policy. The overwrite option must be specified or an error occurs if the destination policy exists.

CLI Syntax:
config>qos> copy port-scheduler-policy src-name dst-name [overwrite]
 
*A:Dut-1>config>qos# port-scheduler-policy psp create 
*A:Dut-1>config>qos>port-sched-plcy# mode wdrr 
*A:Dut-1>config>qos>port-sched-plcy# queue 1 weight 1 
*A:Dut-1>config>qos>port-sched-plcy# queue 2 weight 2 
*A:Dut-1>config>qos>port-sched-plcy# queue 3 weight 5 
*A:Dut-1>config>qos>port-sched-plcy# info 
----------------------------------------------
            mode wdrr
            queue 2 weight 2
            queue 3 weight 5
----------------------------------------------
*A:Dut-1>config>qos>port-sched-plcy# exit 
*A:Dut-1>config>qos# exit 
*A:Dut-1>config# qos copy port-scheduler-policy psp psp1 
*A:Dut-1>config# qos copy port-scheduler-policy psp psp1 
MINOR: CLI Destination "psp1" exists - use {overwrite}.
 
*A:Dut-1>config# show qos port-scheduler-policy          
===============================================================================
Port Scheduler Policies
===============================================================================
Policy-Id                     Description                             Mode     
-------------------------------------------------------------------------------
default                       Default Port Scheduler policy.         STRICT   
psp                                                                   WDRR     
psp1                                                                WDRR     
===============================================================================
*A:Dut-1>config#    
 
 
*A:Dut-1>config# show qos port-scheduler-policy psp 
===============================================================================
QoS Port Scheduler Policy
===============================================================================
Policy-Name       : psp
Accounting        : packet-based                                               
Mode              : WDRR                                                       
Last changed      : 04/12/2001 02:04:16                                        
Queue 1 Weight:   : 1                                                          
Queue 2 Weight:   : 2                                                          
Queue 3 Weight:   : 5                                                          
Queue 4 Weight:   : 1                                                          
Queue 5 Weight:   : 1                                                          
Queue 6 Weight:   : 1                                                          
Queue 7 Weight:   : 1                                                          
Queue 8 Weight:   : 1                                                          
===============================================================================
*A:Dut-1>config# 
 
 
*A:Dut-1>config# show qos port-scheduler-policy psp1 
===============================================================================
QoS Port Scheduler Policy
===============================================================================
Policy-Name       : psp1
Accounting        : packet-based                                               
Mode              : WDRR                                                       
Last changed      : 04/12/2001 02:05:00                                        
Queue 1 Weight:   : 1                                                          
Queue 2 Weight:   : 2                                                          
Queue 3 Weight:   : 5                                                          
Queue 4 Weight:   : 1                                                          
Queue 5 Weight:   : 1                                                          
Queue 6 Weight:   : 1                                                          
Queue 7 Weight:   : 1                                                          
Queue 8 Weight:   : 1                                                          
===============================================================================
*A:Dut-1>config# 

13.2.2. Editing QoS policies

To prevent configuration errors use the copy command to make a duplicate of the original policy to a work area, make the edits, and then overwrite the original policy.