IP Address based QOS on 4900M

[btel]

Hello,

We have a Cisco 4900M which we use for L3. On E1/1 we have the UPLINK provider doing BGP and on E1/8 we have the Downlink, towards the server. We would like to give certain bandwidth priority for traffic from our network towards the internet, on port E1/8. So we would like to give for example to prefix 192.168.4.0/24 a bigger importance than to 192.168.5.0/24. So that any traffic 192.168.4.0/24 would do, it would have priority against any traffic done by 192.168.5.0/24 or any other IP prefix/address.

Thanks!

[Joseph W. Doherty]

I believe you should be able to assign relative priorities on egress ports. Likely, you need to identify the network on ingress, and they prioritize on egress.

From what you described, though, you may have misstated a requirement, as you have E1/8 as a downlink to servers, but you what to prioritize it going toward the Internet?

[btel]

I was thinking either prioritize incoming packets (from the servers to the E1/8), either prioritize outgoing packets before leaving for the ISP, on E1/1. 

[Joseph W. Doherty]

What do you mean by prioritizing incoming packets?

[btel]

I mean allow packets from specific IP ranges from some of our servers to be delivered first, before other ranges. Something like a "priority" command. 

[Joseph W. Doherty]

Yes, that should be doable. I believe the 4900M has the same architecture as the earlier 4500 sup modules. The IOS manuals for your version should have a chapter on QoS configuration. Suspect it will support an ingress policy for traffic classification and a number of hardware egress queues to which you can direct traffic, each should be somehow configurable for how that queue is treated relative to the others. Understand, though, generally traffic isn't actually prioritized until there's interface congestion.

If you can identify the specific IOS version, I could probably provide reference link(s) to the QoS material. If you need assistance understanding how to use the QoS features, you probably should post a new question.