I'm still in process of understanding fully QoS, the portion i'm still trying to fully understand in my lab is:
I've got an Access switch, using auto qos on the access ports
On my port-channel uplink to Core, for my voice traffic, i'm setting a priority bandwidth, and marking dscp ef, and cos 3
On my Core, i'm trusting the cos value on the port-channel (mls qos trust cos), and ethernet uplinks for my Access switches.
1. So the way i understand it is, my voice traffic's ethernet frame is now properly marked w/dscp & cos values appropriate
for voice. The core trusts the cos value coming from my access switch. Does it trust the dscp values as well, even
though no explicit cmd was applied to auto trust?
2. What is the best method, if it's a command or a packet sniff, to view that traffic is correct being classified in a class map,
and that the markings do get applied.
3. My Access switch does not support 'auto qos trust dscp'. i have 'auto qos trust cos'. I have a Tandberg video unit, which
can do dscp markings. Whats are a few options, and pros and cons of ensuring this traffic is correctly marked?
should i mark all traffic from the port with a specific CoS value
or should i classify the video traffic, and manually set a dscp & cos value, and add it to the service-policy on the uplink