Qos Rewrite Ip Dscp - Cisco 4500M Command Reference Manual

Chapter2 Cisco IOS Commands for the Catalyst 4500 Series Switches

qos rewrite ip dscp

To enable DSCP rewrite for IP packets, use the qos rewrite ip dscp command. To disable IP DSCP
rewrite, use the no form of the command.
Syntax Description
This command has no arguments or keywords.
Defaults
IP DSCP rewrite is enabled.
Command Modes
Global configuration
Command History Release
12.2(18 )EW
Usage Guidelines
If you disable IP DSCP rewrite and enable QoS globally, the following events occur:
•
•
•
If you disable QoS, the CoS and DSCP of the incoming packet are preserved and are not rewritten.
Examples
The following example shows how to disable IP DSCP rewrite:
Switch(config)# no qos rewrite ip dscp
Switch(config)#
Related Commands
qos (global configuration mode)
show qos
78-16201-01
qos rewrite ip dscp
no qos rewrite ip dscp
Modification
Support for this command was introduced on the Catalyst 4500 series switch.
The ToS byte on the IP packet is not modified.
Marked and marked-down DSCP values are used for queueing.
The internally derived DSCP (as per the trust configuration on the interface or VLAN policy) is used
for transmit queue and Layer 2 CoS determination. The DSCP is not rewritten on the IP packet
header.
Catalyst4500 Series SwitchCiscoIOS Command Reference—Release 12.2(18)EW
qos rewrite ip dscp
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