I am confused about egress queuing on 3560's. Assuming the following:
R1 fa0/0 --- fa0/1 SW1 fa0/19 --- fa0/19 SW2 fa0/2 --- fa0/1 R2
!SW1 config
mls qos
no mls qos rewrite ip dscp
!
interface FastEthernet0/19
speed 10
!
i generate icmp traffic from R1 to R2 with dscp 44. If I issue show mls qos int fa0/19 stat I see the values for dscp 44 ingress and egress incrementing so we know the marking is being honored. Based on all of the default values these packets should be going into output queue 1 which is shaped to 400k (based on a 10M interface).
Why is it that I see output rates well above 400k, like 6M? The shaper is always active even if there is no congestion, correct?
if I add srr-queue bandwidth limit 20 to the interface I see the output rate drop significantly as I would expect. While the output rate isn't the full 2M it is still well above the 400k.
What am I missing here?