QOS - wrr-queue bandwidth

[bflowers]

I have Qos setup on my 3550 with the EMI image. Can someone help me determine what I need to set the wrr-queue bandwidth at. Its 4 numbers with spaces between assigned to queues 1 2 3 4. I have 2 voice and 1 data vlan. I want the data to drop when I have requests for calls. But I don't want to give the Voice1 more than 20% voice2 more than 10% and about 70 to 80 for the data vlan.

Any information would be appreciated.

Thanks,

[andrew.butterworth]

If you read any of the AVVID design guides (have a search on CCO) Cisco generally recommend a Strict Priority Queue for Voice Media traffic. The default configuration when QoS is enabled on a 3550 is each port has 4 WRR queues each allocated 25% of the bandwidth and each queue having the same weight. The CoS to queue mapping is 0,1 in Q1, 2,3 in Q2, 4,5 in Q3 and 6,7 in Q4. If the Priority Queue is enabled this queue is serviced until empty, so this is ideally where you would put any Voice Media traffic (usually CoS/ToS=5, DSCP 40 or 46).

I would recommend that you familiarise yourself with the 3550 QoS configuration guide on CCO - it might take a few reads but it is worth it.