i'm trying to enable qos on a 6509 and I am not sure when to use port based or vlan based qos. currently i have a 16 gigabit port module, and each port is configured with a 2 vlans (voice and data) and is a trunk port. i'm trying to do qos based on incoming cos. so do i need to use vlan-based (because I have multiple vlans on the trunk), or will port-based qos look at all cos values on packets on all the vlans on a given port? my thinking is that port-based will do qos on all vlans on the whole port, while vlan-based could get more granular-allowing you to do different qos on different vlans on a trunk. but maybe i'm way off. any clarification is appreciated. thanks.
bill