QOS , when will it effect the traffic on a router?

[vikram_anumukonda]

Hello,

with the qos configuration (CBWFQ) in place on a router , will it be effective only when there is congestion ? or will it take effect even without congestion ? on the network.

thanks,

Vikram

[Brandon Buffin]

QoS mechanisms take affect when the number of packets exceeds the length of the TX Ring/Hardware Queue. So, some amount of congestion must exist for CBWFQ to have an effect.

Hope this helps. If so, please rate the post.

Thanks,

Brandon

[vikram_anumukonda]

Hello bbuffin,

The reply was helpful and it has cleared my confusion.

Thanks,

Vikram

[spremkumar]

Hi

In addition to neat n short explaination already done by brandon i would like to add few lines to that.

You have gotta 2 queues up one is Hardware queue which can be tweaked using tx ring config line.

It depends on the hardware which you gonna useup over there in your equipment.

The second one is the S/W queues which you configure up manually which is basically CBWFQ or WFQ etc.,

In normal conditions of having only one queue thats with ur hardware queue and no software queues configured and if ur hardware queues gets filled up then you face probs..

if you gotta software queues configured in addition with the h/w queues and once ur h/w queue is filled up ur s/w gets into action and help to avoid the congestion there..

regds