QoS help - non voice related

[treese]

I have a site connected with a transparent LAN circuit with minimal bw.  We just deployed some servers that sync across the link but saturates the connection sometimes.  The traffic is mostly SSL .  I need to configured some traffic control and believe the best way to do this is to configure qp2 and qp3 and create an ACL with the 2 sources and single destination for the attributes then assign to the correct qp and physical port on the switch.  If this is the recommended way to do this I would like to know.  Also I’m having trouble understanding the min and max bandwidth.  I plan on applying the config ingress too.  If I give each source a minimum of 20 and max of 50 then essentially the pipe could be over subscribed if both source servers kicked off at the same time.  The sync are not on a schedule.

configure qosprofile QP2 minbw 20 maxbw 50 ports 1:1
configure qosprofile QP3 minbw 20 maxbw 50 ports 2:1

entry WEB1-QP2 {
if match all {
    source-address 2.2.2.2/32 ;
    destination-address 1.1.1.1/32 ;
}
then {
    qosprofile QP2 ;
}
}
entry WEB2-QP3 {
if match all {
    source-address 3.3.3.3/32 ;
    destination-address 1.1.1.1/32 ;
}
then {
    qosprofile QP3 ;
}
}

The devices on each end are 440’s and we do have other traffic traversing the link.  These 2 servers are the ones that saturate the link but other traffic is important and don’t want to degrade the remaining traffic.  This traffic is not voice related.  If you could point me to the right solution or forum and have suggestions it would be most appreciated.  Thank you

[treese]

On egress rate-limiting the packets comes in hits the meter then goes out lower.  This could still be an issue your mentioning because the over port could still be saturated because of this?  I could set up the meter on both sides?

[treese]

Yes the 2 servers that can starve the network sit behind the LAN I don’t manage but the uplink hit my 440 stacks.  From there I have a metro E fiber circuit that sits between the sites.  I’ll need to set up QoS on it and I think I can use an ACL to send the 2 sources to a 15Mb meter.  The total bw of the link is 20Mb.  I believe after getting your suggestions this is the way to go.  Let me know if I’m off on this.  It’s sort of trial by error because we do plan bumping up the circuit but still want to have some assurance with this traffic.

[FredrikB]

I thought you said you wanted to have the two servers that were syncing to NOT starve other traffic. Which traffic is most important? You could even set up filters that let the servers sync with low prio (specific IP to IP) but other traffic to/from those exact same IPs (servers) to other IPs can have a higher prio. The problem is that the X440 (G2 or not) can only do egress policing, not ingress. If you specify an ingress rate, it will be applied to the traffic when it leaves the switch, not as it enters it:

https://gtacknowledge.extremenetworks.com/articles/How_To/How-to-configure-basic-rate-limiting-on-a-...

For prioritizing to work, you need to configure the egress interface to match the circuit. In your case you need to do this on both sides:

configure port X rate-limit egress 20 Mbps

You can then work with prio to make sure all traffic is forwarded in an acceptable manner. Failing to limit the egress will mean that you still push traffic to the carrier at 1 or 10 Gbps and no prio will be needed by your switch as there will be no queing up of packets. You need to control the queing in order to control which packets that may step ahead of the queue.

[treese]

Would creating a meter percentage and limit the bandwidth that way be a more sound set up?

[treese]

I plan on moving the config to the FW interfaces which are 100Mb each and not the 10Gb uplink.  That way the configs on each side can be the same if I need to build on that side too.  I’ve ran the this setup before but my question is more about when setting up the qp’s with config I put out there could hamper the connection at peak times. 

configure qosprofile QP2 minbw 20 maxbw 50 ports 1:1
configure qosprofile QP3 minbw 20 maxbw 50 ports 2:1

How do I give priority to 2 servers with say subnet of .152 over all other traffic.  Lots of different traffic traverse this link.  Would rate limiting be the way to go?  What would this config look like?  Thank you