Cisco Catalyst 2960 Series User Manual

The egress queue default settings are suitable for most situations. You should change them only when you
have a thorough understanding of egress queues and if these settings do not meet your QoS solution.
Note
Beginning in privileged EXEC mode, follow these steps to map DSCP or CoS values to an egress queue and
to a threshold ID. This procedure is optional.
SUMMARY STEPS
1.
configure terminal
2.
Use one of the following:
•
mls qos srr-queue output dscp-map queue queue-id threshold threshold-id dscp1...dscp8
•
mls qos srr-queue output cos-map queue queue-id threshold threshold-id cos1...cos8
3.
end
4.
show mls qos maps
5.
copy running-config startup-config
DETAILED STEPS
PurposeCommand or Action
Enters global configuration mode.configure terminal
Example:
Switch# configure terminal
Step 1
Maps DSCP or CoS values to an egress queue and to a threshold ID.Use one of the following:
Step 2
By default, DSCP values 0–15 are mapped to queue 2 and threshold 1. DSCP values
16–31 are mapped to queue 3 and threshold 1. DSCP values 32–39 and 48–63 are
•
mls qos srr-queue output
dscp-map queue queue-id
mapped to queue 4 and threshold 1. DSCP values 40–47 are mapped to queue 1
and threshold 1.
threshold threshold-id
dscp1...dscp8
By default, CoS values 0 and 1 are mapped to queue 2 and threshold 1. CoS values
2 and 3 are mapped to queue 3 and threshold 1. CoS values 4, 6, and 7 are mapped
to queue 4 and threshold 1. CoS value 5 is mapped to queue 1 and threshold 1.
•
mls qos srr-queue output
cos-map queue queue-id
threshold threshold-id
cos1...cos8
•
For queue-id, the range is 1 to 4.
If you enabled 8 egress queues using the mls qos srr-queue output
queues 8 global configuration command, then the queue-id range
would be from 1 to 8.
Note
Example:
Switch(config)# mls qos srr-queue
•
For threshold-id, the range is 1 to 3. The drop-threshold percentage for
threshold 3 is predefined. It is set to the queue-full state.
output
dscp-map queue 1 threshold 2 10
11
•
For dscp1...dscp8, enter up to eight values, and separate each value with a
space. The range is 0 to 63.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
622
How to Configure QoS

Cisco Catalyst 2960 Series Specifications

General

Layer	Layer 2
Power over Ethernet (PoE)	Available on some models
RAM	128 MB
Flash Memory	32 MB
MAC Address Table Size	8000
Operating Temperature	0°C to 45°C (32 to 113°F)
Ports	24 or 48 x 10/100/1000