KB.15.15

Interaction with other software features

After applying a QoS policy to an interface, an error message appears if there are not sufficient

hardware resources to support the policy. In this case, use the show resources command to

verify the amount of resources that are currently in use and the resources available on the switch.

QoS policies share the same hardware resources with other software features, such as mirroring

policies, ACLs, virus throttling, the management VLAN, and so on.

Use the displayed information to decide whether to re-prioritize current resource usage by

re-configuring or disabling software features to free the resources reserved for less important

features.

For more information, see the Management and Configuration Guide for your switch.

Notes on changing priority settings

If you try to modify the priority associated with a DSCP codepoint in a DSCP policy using the qos

dscp-map priority command, and if the DSCP policy is currently used by one or more global

QoS or classifier-based QoS policies, the following error message is displayed:

Cannot modify DSCP Policy codepoint - in use by other qos rules.

In this case, enter the following QoS show commands to identify in which global and classifier-based

QoS configurations the DSCP policy is currently used:

show policy qos-policy

show qos tcp-udp-port-priority

show qos device-priority

show qos type-of-service

show qos protocol

show qos vlan

show qos port-priority

After determining the QoS configurations in which the DSCP-priority mapping is used, you can

either delete a QoS configuration and reset the DSCP-priority mapping to No-override, or

change either the 802.1p priority or the codepoint used in the QoS configuration.

Interaction with other software features 257