Specifications

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Catalyst 2970 Switch Software Configuration Guide
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Chapter 27 Configuring QoS
Configuring Standard QoS
Configuring the Egress Expedite Queue
Beginning in Cisco IOS Release 12.1(19)EA1, you can ensure that certain packets have priority over all
others by queuing them in the egress expedite queue. SRR services this queue until it is empty before
servicing the other queues.
Beginning in privileged EXEC mode, follow these steps to enable the egress expedite queue. This
procedure is optional.
To disable the egress expedite queue, use the no priority-queue out interface configuration command.
This example shows how to enable the egress expedite queue when the SRR weights are configured. The
egress expedite queue overrides the configured SRR weights.
Switch(config)# interface gigabitethernet0/4
Switch(config-if)# srr-queue bandwidth shape 25 0 0 0
Switch(config-if)# srr-queue bandwidth share 30 20 25 25
Switch(config-if)# priority-queue out
Switch(config-if)# end
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
mls qos Enable QoS on a switch.
Step 3
interface interface-id Enter interface configuration mode, and specify the egress interface.
Step 4
priority-queue out Enable the egress expedite queue, which is disabled by default.
When you configure this command, the SRR weight and queue size ratios
are affected because there is one fewer queue participating in SRR. This
means that weight1 in the srr-queue bandwidth shape or the srr-queue
bandwidth share command is ignored (not used in the ratio calculation).
Step 5
end Return to privileged EXEC mode.
Step 6
show running-config Verify your entries.
Step 7
copy running-config startup-config (Optional) Save your entries in the configuration file.