My test scenario is that voip traffic is going to traverse between one site to another. Mostly the voice gateways are split across the sites. Now in the setup 3750 are interconnecting the intersite links on a LES widely on 100Mbps. I was more worried about the priority queue in the c3750, its a strict priority queue, so the SRR will not service other queues until priority queue is free. Incase of an edge where its connecting to another site, inter site voice traffic can accumulate, so wouldnt the c3750 be constantly be servicing the priority queue, because lots of people might be on calls? Or have I understood the SRR strict priority wrong? Incase we disbale the priority queue , would just shape( weight ) command help in serviceing the voip traffic more quickly than data?
Thank you so much Jon for your inputs. Yes I am also waiting for the info but just got this weird thinking when testing the setup.
"You allocate the bandwidth needed to cater for the number of calls, hence you need to know the number of calls, the codec etc. to work out how much bandwidth is needed." your quote refers to the actual WAN bandwith I assume, or is it to the SRR queue bandwidth. If its SRR queue bandwidth, say I need 10M for voice so I should use the srr-queue shape 10 0 0 0 to allocate 10M to the voip traffic. But priority queue out will ignore this command anyways, this is where exactly I am confused. Sorry
No need to apologise, catalyst QOS is not one of the easier subjects to understand
If you need 10M for VOIP then you need to rate-limit the amount of VOIP traffic on the ingress ie. coming into your switch so it cannot exceed 10M. You cannot do the rate-limiting on the egress interface because rate-limiting is not supported on egress. So you don't specify a bandwidth on the egress priority queue you limit the amount of priority traffic as it enters the switch.