Attaching a traffic policy to an interface – Cisco 15327 User Manual

Page 224

Advertising
background image

14-16

Ethernet Card Software Feature and Configuration Guide, R7.2

Chapter 14 Configuring Quality of Service

Attaching a Traffic Policy to an Interface

Attaching a Traffic Policy to an Interface

Use the service-policy interface configuration command to attach a traffic policy to an interface and to
specify the direction in which the policy should be applied (either on packets coming into the interface
or packets leaving the interface). Only one traffic policy can be applied to an interface in a given
direction.

Router (config-pmap-c)# priority

kbps

Specifies low latency queuing for the currently selected class.
This command can only be applied to an output. When the
policy-map is applied to an output, an output queue with strict
priority is created for this class. The only valid rate choice is in
kilobits per second.

Note

This priority command does not apply to the default
class.

Note

When using the priority action, the traffic in that class
is given a 100 percent CIR, regardless of the rate
entered as the priority rate. To ensure that other
bandwidth commitments are met for the interface, a
policer must be configured on the input of all interfaces
that might deliver traffic to this output class, limiting
the peak rate to the priority rate entered.

Note

The true configurable bandwidth in kilobits or megabits
per second is per port and depends on how the
ML-Series card is configured. The show interface
command shows the maximum bandwidth of a port (for
example, BW 100000 Kbit). The sum of all bandwidth
and priority actions applied to the interface, plus the cos
priority-mcast bandwidth, is not allowed to exceed the
maximum bandwidth of the port.

Router (config-pmap-c)# set cos

cos-value

Specifies a CoS value or values to associate with the packet.
The number is in the range from 0 to 7.

This command can only be used in a policy-map applied to an
output. It specifies the VLAN CoS priority to set for the
outbound packets in the currently selected class. If QinQ is
used, the top-level VLAN tag is marked. If outbound packets
have no VLAN tag, the action has no effect. This action is
applied to the packet after any set-cos action done by a policer,
and therefore overrides the CoS set by a policer action.

If a packet is marked by the policer and forwarded out an
interface that also has a set-cos action assigned for the traffic
class, the value specified by the police action takes precedence
in setting the IEEE 802.1p CoS field.

This command also sets the CoS value in the Cisco proprietary
RPR header for packets exiting the ML-Series on the Cisco
proprietary RPR interface.

Table 14-2

Traffic Policy Commands (continued)

Command

Purpose

Advertising