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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter36 Configuring QoS Configuring Standard QoS
In some situations, you can prevent a PC connected to the Cisco IP Ph one f ro m ta king advantage o f a
high-priority data queue. You can use the switchport priority extend cos interface configuration
command to configure the telephone through the switch CLI to override the priority of the traffic
received from the PC.
Beginning in privileged EXEC mode, follow these steps to enable trusted bound ar y on a po rt:
To disable the trusted boundary feature, use the no mls qos trust device interface configuration
command.
Enabling DSCP Transparency Mode
The switch supports the DSCP transparency feature. It affects only the DSC P f ield of a pack et at e gr ess.
By default, DSCP transparency is disabled. The switch modifies the DSCP field in an inc omin g pa cket,
and the DSCP field in the outgoing packet is based on the qua lity of servi ce (Qo S) c on figurat ion,
including the port trust setting, policing and marking, and the DSCP-to-DSCP mutation map.
If DSCP transparency is enabled by using th e no mls qos rewrite ip dscp command, the switch does not
modify the DSCP field in the incoming packet, and the DSCP field in the outg oing packet is the same as
that in the incoming packet.
Note Enabling DSCP transparency does not affect the port trust settings on IEEE 802.1Q tunneling ports.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 cdp run Enable CDP globally. By default, CDP is enabled.
Step3 interface interface-id Specify the port connected to the Cisco IP Phone, and enter interface
configuration mode.
Valid interfaces include physical ports.
Step4 cdp enable Enable CDP on the port. By default, CDP is enabled.
Step5 mls qos trust cos
mls qos trust dscp
Configure the switch port to trust the CoS value in traffic received from the
Cisco IP Phone.
or
Configure the routed port to trust the DSCP value in traffic received from
the Cisco IP Phone.
By default, the port is not trusted.
Step6 mls qos trust device cisco-phone Specify that the Cisco IP Phone is a trusted device.
You cannot enable both trusted boundary and auto-QoS (auto qos voip
interface configuration command) at the same time; they are mutually
exclusive.
Step7 end Return to privileged EXEC mode.
Step8 show mls qos interface Verify your entries.
Step9 copy running-config startup-config (Optional) Save your entries in the configuration file.