Port channels on different line card types and qos

If you enable qos you perform buffer carving (allocation of buffers) and the creation of queues. Many card based hardware platforms like the 6500 have different queueing and buffer architectures between different card types. What this means is that if you enable QoS ports that were in a port channel get suspended because the QoS parms do not match. If you do not run LACP you can end up with a great deal of trouble.