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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 38 Configuring Standard QoS
How to Configure Standard QoS
If you disable QoS by using the no mls qos global configuration command, the CoS and DSCP values
are not changed (the default QoS setting).
If you enter the no mls qos rewrite ip dscp global configuration command to enable DSCP transparency
and then enter the mls qos trust [cos | dscp] interface configuration command, DSCP transparency is
still enabled.
Configuring the DSCP Trust State on a Port Bordering Another QoS Domain
To ensure a consistent mapping strategy across both QoS domains, you must perform this procedure on
the ports in both domains:
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 mls qos Enables QoS globally.
Step 3 no mls qos rewrite ip dscp Enables DSCP transparency. The switch is configured to not modify the
DSCP field of the IP packet.
Step 4 end Returns to privileged EXEC mode.
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 mls qos map dscp-mutation
dscp-mutation-name in-dscp to out-dscp
Modifies the DSCP-to-DSCP-mutation map.
The default DSCP-to-DSCP-mutation map is a null map, wh ich maps
an incoming DSCP value to the same DSCP value.
dscp-mutation-name—Enters the mutation map name. You can
create more than one map by specifying a new name.
in-dscp—Enters up to eight DSCP values separated by spaces.
Then enter the to keyword.
out-dscp—Enters a single DSCP value.
The DSCP range is 0 to 63.
Step 3 interface interface-id Specifies the port to be trusted, and enters interface configuration
mode.
Valid interfaces include physical ports.
Step 4 mls qos trust dscp Configures the ingress port as a DSCP-trusted port. By default, the port
is not trusted.
Step 5 mls qos dscp-mutation
dscp-mutation-name
Applies the map to the specified ingress DSCP-trusted port.
dscp-mutation-name—Specifies the mutation map name created in
Step 2.
You can configure multiple DSCP-to-DSCP-mutation maps on an
ingress port.
Step 6 end Returns to privileged EXEC mode.