Help with simple QoS? 80/20

[meieltsptx]

Hi,

I'm looking around the internet to configure a basic config for QoS. I'm having some trouble to find a good example without reading 40.000 pages on VoiP QoS and Cisco documentation which is very confusing for me. As my switch (2960) doesn't fully support MQC it looks like the only option i have is SRR egress queueing. 

I am used to shape my traffic by using the max bandwidth command or configuring a shaper. I'm quite in a hurry so reading like 40K pages about QoS isn't really an option, it seems like a big study to find out how this "legacy"-form of QoS works :( . I'd like to split my traffic 80/20 or 90/10. The "bla" traffic should be the 10% of the traffic while the 90% will be a big storage copy over a 1gb link.

its : 

[Switch1] <----1gbps fiber ------> [Switch2]

This is what i've got so far, but i'm not really familiar with this kind of QoS... 

ip access-list extended bla
permit tcp 10.177.0.0 0.0.0.255 any any

class-map match-all bla
match access-group name bla

policy-map QOS
class bla
set dscp ef
class class-default
set dscp default
exit

int gi1/0/1
description link to other side
service-policy output QOS

Any help on how i should configure the 90/10 split on the egress interface would be greatly appreciated.

[Joseph W. Doherty]

As you've already noted, the 2960 does not support MQC for egress policies.  It has 4 hardware queues that are enabled when you enable QoS globally.  You can direct traffic to those 4 queues based on L2 CoS or L3 DSCP (recommend the latter).  (NB: you don't have to use all 4 queues.)  You can set relative bandwidth ratios between the queues.  You can also make the first queue a PQ.  You can also shape individual queues.  You can also "shape" the whole port.

When you enable global QoS, the 2960, by default, will "erase" ingress L2 CoS or L3 DSCP, unless you trust it (or set it).  You can use an ingress policy.

I would recommend you set up a 4 queue model, with 1st queue configured for PQ.  2nd queue can be for foreground traffic, 3rd queue can be for BE and 4th queue can be for background traffic.  Ratios might be something like 89:9:1.

Use the 1st queue for stuff like VoIP bearer traffic.  2nd queue for really important and light bandwidth usage traffic, e.g. VoIP control traffic, 4th queue for bulk/bandwidth-saturating traffic.

By default, the 2960 will map specific L2 CoS and/or L3 DSCP to the 4 hardware queues.