Cisco Catalyst 3750 Metro - Mls Qos Dscp-Mutation

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Catalyst 3750 Metro Switch Command Reference
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Chapter 2 Catalyst 3750 Metro Switch Cisco IOS Commands
mls qos dscp-mutation
mls qos dscp-mutation
Use the mls qos dscp-mutation interface configuration command to apply a Differentiated Services
Code Point (DSCP)-to-DSCP-mutation map to a DSCP-trusted port. Use the no form of this command
to return the map to the default settings (no DSCP mutation).
mls qos dscp-mutation dscp-mutation-name
no mls qos dscp-mutation dscp-mutation-name
Syntax Description
Defaults The default DSCP-to-DSCP-mutation map is a null map, which maps inbound DSCP values to the same
DSCP values.
Command Modes Interface configuration
Command History
Usage Guidelines If two quality of service (QoS) domains have different DSCP definitions, use the
DSCP-to-DSCP-mutation map to translate one set of DSCP values to match the definition of another
domain. You apply the DSCP-to-DSCP-mutation map to the receiving port (ingress mutation) at the
boundary of a QoS administrative domain.
With ingress mutation, the new DSCP value overwrites the one in the packet, and QoS handles the packet
with this new value. The switch sends the packet out the port with the new DSCP value.
You can configure multiple DSCP-to-DSCP-mutation maps on ingress ports.
You apply the map only to DSCP-trusted ports. If you apply the DSCP mutation map to an untrusted
port, to a class of service (CoS) or an IP-precedence trusted port, the command has no immediate effect
until the port becomes DSCP-trusted.
When port trust policies are used with 802.1Q tunneling, all ports sharing the same tunnel VLAN must
be configured with the same trust policy, and the ports involved must use the same DSCP-to-DSCP
mutation map. For more information, see the
“mls qos map” section on page 2-285 and the “mls qos
trust” section on page 2-312.
dscp-mutation-name Name of the DSCP-to-DSCP-mutation map. This map was previously
defined with the mls qos map dscp-mutation global configuration
command.
Release Modification
12.1(14)AX This command was introduced.