Cisco Catalyst 3750-X Command Reference

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Catalyst 3750-X and 3560-X Switch Command Reference
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Chapter 2 Catalyst 3750-X and 3560-X Switch Cisco IOS Commands
mls qos srr-queue input priority-queue
mls qos srr-queue input priority-queue
Use the mls qos srr-queue input priority-queue global configuration command on the switch stack or
on a standalone switch to configure the ingress priority queue and to guarantee bandwidth on the stack
or internal ring if the ring is congested. Use the no form of this command to return to the default setting.
mls qos srr-queue input priority-queue queue-id bandwidth weight
no mls qos srr-queue input priority-queue queue-id
Syntax Description
Defaults The priority queue is queue 2, and 10 percent of the bandwidth is allocated to it.
Command Modes Global configuration
Command History
Usage Guidelines You should use the priority queue only for traffic that needs to be expedited (for example, voice traffic,
which needs minimum delay and jitter).
The priority queue is guaranteed part of the bandwidth on the stack or internal ring, which reduces the
delay and jitter under heavy network traffic on an oversubscribed ring or stack (when there is more traffic
than the backplane can carry, and the queues are full and dropping frames).
On the Catalyst 3750-X switch, the amount of bandwidth that can be guaranteed is restricted because a
large value affects the entire stack and can degrade the stack performance.
Shaped round robin (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.
To disable priority queueing, set the bandwidth weight to 0, for example, mls qos srr-queue input
priority-queue queue-id bandwidth 0.
queue-id Ingress queue ID. The range is 1 to 2.
bandwidth weight Bandwidth percentage of the stack or internal ring. The range is 0 to 40.
Release Modification
12.2(53)SE2 This command was introduced.

Cisco Catalyst 3750-X Specifications

General

Switching Capacity	160 Gbps
Stacking Bandwidth	64 Gbps
Max Stacking Units	9
Layer Support	Layer 2 and Layer 3
Form Factor	Rack-mountable
DRAM	256 MB
Flash Memory	64 MB
Model	Cisco Catalyst 3750-X Series
Ports	24 or 48 10/100/1000 Ethernet ports
Uplink Interfaces	4 SFP or 2 SFP+
Features	StackWise Plus, EnergyWise
Image	IP Base or IP Services
Operating Temperature	0 to 40°C
Operating Humidity	10 to 85% noncondensing