QoS on the Cisco 3925

[Oleg Volkov]

Dear Sirs.

I have two data centers and L3 VPN tunnel between them.
But I have only 100Mbps links to provider network.
Also I have two user groups:
1. High priority.
2. Normal priority.
I can use policing on the 3925 routers and limit maximum speed of the normal priority traffic (for example - 60Mbps) but if channel is free, it is not good.
I want to do, to normal priority traffic can use full bandwith (100Mbps) if no high priority traffic present. And if high priority traffic is present, normal priority traffic can use for example 50% of bandwith.
Also I can use QoS mechanism on the Nexus and 6500, because their SVI interface is default gateways for users workstation.
What best method for achieving my goal?

Thanks!

[Joseph W. Doherty]

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Posting

If your interface is running at 100 Mbps, and your provider doesn't cap at a lower rate, a CBWFQ on you egress interface should do the trick.

On your tunnel, add qos pre-classify.

On your physical interface, add service-policy output YouNameIt.

Also add:

class-map match-all HiPriority

match ...

policy-map YouNameIt

class HiPriority

bandwidth percent 50

fair-queue

class class-default

bandwidth percent 50

fair-queue