Configuring The Dscp-To-Cos Map - Cisco Catalyst 3750-X Software Configuration Manual

Chapter 39 Configuring QoS

Configuring the DSCP-to-CoS Map

You use the DSCP-to-CoS map to generate a CoS value, which is used to select one of the four egress
queues.
Table 39-14
Table 39-14
DSCP Value
0–7
8–15
16–23
24–31
32–39
40–47
48–55
56–63
If these values are not appropriate for your network, you need to modify them.
Beginning in privileged EXEC mode, follow these steps to modify the DSCP-to-CoS map. This
procedure is optional.
Command
Step 1
configure terminal
Step 2 mls qos map dscp-cos dscp-list to cos
Step 3
end
Step 4
show mls qos maps dscp-to-cos
Step 5
copy running-config startup-config
To return to the default map, use the no mls qos dscp-cos global configuration command.
This example shows how to map DSCP values 0, 8, 16, 24, 32, 40, 48, and 50 to CoS value 0 and to
display the map:
Switch(config)# mls qos map dscp-cos 0 8 16 24 32 40 48 50 to 0
Switch(config)# end
Switch# show mls qos maps dscp-cos
Dscp-cos map:
OL-21521-01
shows the default DSCP-to-CoS map.
Default DSCP-to-CoS Map
CoS Value
0
1
2
3
4
5
6
7
Purpose
Enter global configuration mode.
Modify the DSCP-to-CoS map.
•
•
The DSCP range is 0 to 63; the CoS range is 0 to 7.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
d1 : d2 0 1 2 3 4
---------------------------------------
0 : 00 00 00 00 00 00 00 00 00 01
1 : 01 01 01 01 01 01 00 02 02 02
2 : 02 02 02 02 00 03 03 03 03 03
For dscp-list, enter up to eight DSCP values separated by spaces.
Then enter the to keyword.
For cos, enter the CoS value to which the DSCP values correspond.
5 6 7 8 9
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
Configuring Standard QoS
39-73