Cisco Catalyst 3750-E - Page 941

37-87
Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-08
Chapter 37 Configuring QoS
Configuring Standard QoS
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.
To return to the default DSCP output queue threshold map or the default CoS output queue threshold
ma
p, use the no mls qos srr-queue output dscp-map or the no mls qos srr-queue output cos-map
global configuration command.
This example shows how to map DSCP values 10 and 11 to egress queue 1 and to threshold 2:
Switch(config)# mls qos srr-queue output dscp-map queue 1 threshold 2 10 11
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
mls qos srr-queue output dscp-map
queue queue-id threshold threshold-id
dscp1...dscp8
or
mls qos srr-queue output cos-map
queue qu
eue-id threshold threshold-id
cos1...cos8
Map DSCP or CoS values to an egress queue and to a threshold ID.
By default, DSCP values 0–15 are mapped to queue 2 and threshold 1.
D
SCP values 16–31 are mapped to queue 3 and threshold 1. DSCP values
32–39 and 48–63 are mapped to queue 4 and threshold 1. DSCP values
40–47 are mapped to queue 1 and threshold 1.
By default, CoS values 0 and 1 are mapped to queue 2 and threshold 1.
CoS v
alues 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.
• For queue-id, the range is 1 to 4.
• 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.
• For dscp1...dscp8, enter up to eight values, and separate each value
with a space. The range is 0 to 63.
• For cos1...cos8, enter up to eight values, and separate each value with
a space. The range is 0 to 7.
Step 3
end Return to privileged EXEC mode.
Step 4
show mls qos maps Verify your entries.
The DSCP output queue threshold map appears as a matrix. The d1
c
olumn specifies the most-significant digit of the DSCP number; the d2
row specifies the least-significant digit in the DSCP number. The
intersection of the d1 and the d2 values provides the queue ID and
threshold ID; for example, queue 2 and threshold 1 (02-01).
The CoS output queue threshold map shows the CoS value in the top row
and
the corresponding queue ID and threshold ID in the second row; for
example, queue 2 and threshold 2 (2-2).
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.