Cisco 7604

41-92
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 41 Configuring PFC QoS
Configuring PFC QoS
To configure the trust state of a port, perform this task:
When configuring the trust state of a port, note the following information:
• With no other keywords, the mls qos trust command is equivalent to mls qos trust dscp.
• With Release 12.2(18)SXF5 and later releases, you can use the mls qos trust dscp command to
enable DSCP-based receive-queue drop thresholds on WS-X6708-10GE ports (see the “Configuring
DSCP-Based Queue Mapping” section on page 41-100). To avoid dropping traffic because of
inconsistent DSCP values when DSCP-based queue mapping is enabled, configure ports with the
mls qos trust dscp command only when the received traffic carries DSCP values that you know to
be consistent with network policy.
• The mls qos trust cos command enables CoS-based receive-queue drop thresholds. To avoid
dropping traffic because of inconsistent CoS values, configure ports with the mls qos trust cos
command only when the received traffic is ISL or 802.1Q frames carrying CoS values that you know
to be consistent with network policy.
• With Release 12.2(17b)SXA and later releases, you can configure IEEE 8021.Q tunnel ports
configured with the mls qos trust cos command to use a mutated CoS value instead of the received
CoS value (“Configuring Ingress CoS Mutation on IEEE 802.1Q Tunnel Ports” section on
page 41-85).
• Use the no mls qos trust command to set the port state to untrusted.
This example shows how to configure Gigabit Ethernet port 1/1 with the trust cos keywords:
Router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)# interface gigabitethernet 1/1
Router(config-if)# mls qos trust cos
Router(config-if)# end
Router#
This example shows how to verify the configuration:
Router# show queueing interface gigabitethernet 1/1 | include trust
Trust state: trust COS
Router#
Command Purpose
Step 1
Router(config)# interface {{ type
1
slot/port } |
{port-channel
number }}
1. type = ethernet, fastethernet, gigabitethernet, tengigabitethernet, ge-wan, pos, or atm.
Selects the interface to configure.
Step 2
Router(config-if)# mls qos trust [dscp |
ip-precedence | cos
2
]
2. Not supported for serial, pos or atm interface types.
Configures the trust state of the port.
Router(config-if)# no mls qos trust
Reverts to the default trust state (untrusted).
Step 3
Router(config-if)# end
Exits configuration mode.
Step 4
Router# show queueing interface type
1
slot/port |
include Trust state
Verifies the configuration.