QOS Beginner question - Procurve 5412zl

[Rubík]

I am looking for some help with applying QOS to a Procurve 5412zl.  QOS is not something we have used before.  There is an application that communicates with TCP 5003 that is suffering some performance issues (client / server application with the app server located in a datacentre)

I would like to see if we can improve performance through QOS.  My question is whether QOS will even have an effect if there is always spare bandwith over the office<->Datacenter circuit (and there almost always is, even when the application in question is performing poorly)

If applying QOS might improve performance then this is something I would like to try.  I have seen some examples of QOS being applied to vlans however nothing specific to data on a particular port.  IS there a good reference on this?  Do I also need to specify that everything else should run at priority 2 after setting tcp 5003 as priority 1.

All advice welcomed,

[Sietze Reitsma]

First of all (s)low performance of client/server applications can have many causes. Qos will only help if there is a congested network. Other causes can lie in the application itself, latency of long distances round trip delays or the speed and resources of the backend applications and hardware (cpu, memory storage).

Best reference is to read the manual, also entering 'help' after the qos commands in config mode will give you lots of info.

To mark the tcp 5003 traffic to the right priority queue just enter:

5406zl (config)#qos tcp-port ipv4 5003 priority 6

you can also remark the traffic to a DSCP. In that case WAN Qos can handle the traffic in the correct classes.

syntax:

[no] qos {udp-port | tcp-port} [ipv4 | ipv6 | ip-all]           {<PORT> | range <PORT> <PORT>}           { dscp <Codepoint> | priority <Priority> }

The switch has 8 priority queues (from low to high) 1 2 0 3 4 5 6 7

[Rubík]

Thanks for that, very helpful.