Flexible QOS limit for 2 hosts.

roger perkin · ‎10-12-2011

I have 2 x 6500's connected via a 100MB Les circuit between our main and DR sites.

There are 2 nodes which pass 95% of the traffic on this link which is data replication.

I have setup a policer on the port channel to restrict the traffic to 75MB

however the other node is now transmitting and I assume my policy is policing them both to 75, so they actually swamp the link.

What I want to be able to do is to permit nodeA to have 75Mb BW if it is available, however if NodeB starts talking to only allow them 75 between them.

The other 25 is for BAU traffic

sh class-map

Class Map match-any class-default (id 0)

Match any

Class Map match-any S2S (id 2)

Match access-group name S2S

sh policy-map

Policy Map S2S

Class S2S

police cir 70000000 bc 2187500

conform-action transmit

exceed-action drop

Extended IP access list S2S

10 permit ip host 10.251.225.66 any (15 matches)

30 permit ip host 10.251.225.67 any (6 matches)

interface Port-channel100

description Site to Site Connection

service-policy output S2S

Thanks

Roger

Joseph W. Doherty · ‎10-12-2011

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What you desire might not be possible unless you have have the QoS features of a 6500 WAN type card.

Even if you did have complete QoS features, since policer's don't queue, not sure you could do it even then. With full QoS features, you would be able to do something close to what you describe using a shaper and hierarchal policy.

If you're using LAN cards, one that supports at least 2 queues, you could change weights to guarantee 25% bandwidth to BAU traffic, then remaining bandwidth to be split evenly between hosts A and B. (NB: with guarantees, I will often invert the proportions, i.e. guarantee 75% to BAU and 25% to hosts A and B, since either can use the others unused bandwidth.)