QOS settings for different devices

[carl_townshend]

Hi All

When configuring auto QOS for switchports, which settings are best to apply for phones, VC and video devices and uplinks

The phones we use auto qos voip cisco phone, trunks we use auto qos voip trust, what do we use for vc and video?

Cheers

[Mark Malone]

Every change you make creates a different map in terms of auto qos
if you look at this guide it shows you each policy/class setup it will introduce depending how you alter your access port or uplink port
https://www.cisco.com/en/US/docs/switches/lan/catalyst3850/software/release/3.2_0_se/multibook/configuration_guide/b_consolidated_config_guide_3850_chapter_010001.html#reference_520578DE4D9F44949AE2E3704F7BE3F1]

each of these below creates a new map , ios-xe trusts DSCP by default so if your end device is Cisco it will mark it anyway and you dont need to do anything on the switch , Lync also marks the edge traffic , auto qos trust dscp will cover everything too if the end devices mark , if the end devices are not marking you could pick one of the below , i wouldnt have too manay though or you will have a lot of class and policy setups in global config

Auto-QoS Policy and Class Maps
auto qos classify command
auto qos classify police command
auto qos trust command
auto qos trust cos command
auto qos trust dscp command
auto qos video cts command
auto qos video ip-camera command
auto qos video media-player command
auto qos voip cisco-phone command
auto qos voip cisco-softphone command
auto qos voip trust command

[Joseph W. Doherty]

"When configuring auto QOS for switchports, which settings are best to apply for phones, VC and video devices and uplinks"

Generally I recommend against using auto QoS. If you're wondering why, well auto QoS is a QoS configuration that's provided by Cisco that Cisco expects will be useful most of the time. However, without knowing what your traffic mix is and its actual service requirements, Cisco's auto QoS is a crapshoot.

Interestingly, from time-to-time, with new IOS versions, what auto QoS generates differs. Which shows that even without knowing your traffic, QoS is often a moving target.

"The phones we use auto qos voip cisco phone, trunks we use auto qos voip trust, what do we use for vc and video?"

If the video is streaming, you want QoS to try to preclude any packets drops. If the video is "live", like VC, additionally you want your QoS to minimize any queuing delay. I.e. the latter should be treated logically much like VoIP bearer traffic, but often it's much more bandwidth demanding.