Debug to show i/f congestion / service policy applied ?

[ajenks]

I have a service policy applied on a 2600 router ethernet interface, intended to allocate bandwidth when there is congestion. Is there a simple debug command that will indicate when a how often the interface reaches this state and the policy is applied ? rather than relying on the dropped packet count (to see if it is applying) ? I would like a simple output (I can then log) that would indicate how often this condition has occured.

[jackyoung]

Try "debug ip policy" or debug the access-list to determine the hits of ACL if it is PBR.

Or try to use "show policy-map" command to find out the hit of the policy.

Hope this helps.

[wochanda]

There aren't any debugs that'll show you when packets are being queued up in your QoS policy (to have one wouldn't be safe). Instead, by looking at a 'show policy-map interface' you can tell if the interface has been under congestion.

I dont have any sample output, but i'll try to describe where to look. Right underneath the class name you'll see a counter that says "x packets, y bytes". This is the amount of packets that have been classified as being part of that class, but not necessarily the amount of packets that had to be queued as a result of congestion. If you look down about 10 lines you'll see a different counter: "packets matched, bytes matched". This counter is generally lower than the first one I talked about. This counter only increments when the packets were queued up as a result of congestion.

The closer these counters are to each other, the more your interface has been under congestion and thus had to queue the packets up.