Chapter 28
Configuring QoS
Allocating Bandwidth Between the Ingress Queues
You need to specify how much of the available bandwidth is allocated between the ingress queues. The
ratio of the weights is the ratio of the frequency in which the SRR scheduler sends packets from each
queue. The bandwidth and the buffer allocation control how much data can be buffered before packets
are dropped. On ingress queues, SRR operates only in shared mode.
Beginning in privileged EXEC mode, follow these steps to allocate bandwidth between the ingress
queues. This procedure is optional.
Command
Step 1
configure terminal
Step 2
mls qos srr-queue input bandwidth
weight1 weight2
Step 3
end
Step 4
show mls qos interface queueing
or
show mls qos input-queue
Step 5
copy running-config startup-config
To return to the default setting, use the no mls qos srr-queue input bandwidth global configuration
command.
This example shows how to assign the ingress bandwidth to the queues. Priority queueing is disabled,
and the shared bandwidth ratio allocated to queue 1 is 25/(25+75) and to queue 2 is 75/(25+75):
Switch(config)# mls qos srr-queue input priority-queue 2 bandwidth 0
Switch(config)# mls qos srr-queue input bandwidth 25 75
78-16156-01
Purpose
Enter global configuration mode.
Assign shared round robin weights to the ingress queues.
The default setting for weight1 and weight2 is 4 (1/2 of the bandwidth is
equally shared between the two queues).
For weight1 and weight2, the range is 1 to 100. Separate each value with
a space.
SRR services the priority queue for its configured weight as specified by
the bandwidth keyword in the mls qos srr-queue input priority-queue
queue-id bandwidth weight global configuration command. Then, SRR
shares the remaining bandwidth with both ingress queues and services
them as specified by the weights configured with the mls qos srr-queue
input bandwidth weight1 weight2 global configuration command. For
more information, see the
section on page
28-56.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Catalyst 3560 Switch Software Configuration Guide
Configuring Standard QoS
"Configuring the Ingress Priority Queue"
28-55