Auto QOS on 2960-X switches with Avaya phones

[ross.koba]

I'm looking to implement QOS as we have some VOIP quality issues. We have Catalyst 2960-X access switches, and Nexus 9k core switches. Looking through the 2960-x Auto-QOS configuration guide, it seems too easy to be true. There's literally a few commands to run within that guide. Can it be this simple? It can't, right? 

On interfaces connecting to VOIP phones: 

Switch# configure terminal
Switch(config)# interface gigabitethernet x/x/x
Switch(config-if)# auto qos trust dscp
Switch(config-if)# exit

On trunk / uplink interfaces connecting to other switches: 

Switch(config)# interface gigabitethernet x/x/x
Switch(config-if)# auto qos trust
Switch(config-if)# end

*Note* I'm using dscp instead of cisco-phone since they're Avaya phones and not Cisco, assuming they will be using DSCP 46 for signaling and audio. 

[Alex Pfeil]

On your configuration, the trunk should be auto qos trust dscp as well. Yes, it is that easy.  This would be based on the fact that your phones are definitely marking the packets as dscp 46.

You also have to make sure QoS is enabled. mls qos

#show mls qos
QoS is enabled
QoS ip packet dscp rewrite is enabled

Please mark helpful posts.

[ross.koba]

Wow, that's a huge time saver for me, thanks for the quick reply! I did not see any auto-qos options for the Nexus 9k's though. For them I'll have to dig through and build out the mappings and all, I assume?  

[Alex Pfeil]

The default behavior is to keep the dscp marking and queue traffic so you probably do not need additional config on the 9K.

Please mark helpful posts.