Re: qos 3560

[Brian Feeny <bfeeny () mac com>]

You should make sure that any links that go between devices have trust  
set.  In your case if your doing DSCP,
then make sure each link that goes between devices which must carry  
tagged packets have trust dscp set.

Brian

On Nov 12, 2009, at 5:11 AM, Bogdan wrote:

> hello
>
> i am playing with qos on some devices
> - cisco 3560
> - cisco 7609
> and i have some things that i don't seem to understand.
>
> 1. in 3560, i enable mls qos, on the ingress port applyed policy map,
> classify the packets with acl, mark, all good. on the egress ports i  
> use
> srr-queue with shape/share, everything is fine, it is working.
>
> http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_20_se/configuration/guide/swqos.html#wp1028614
>
>
> 2. reset to defaults the 3560
> in 7606 i pick up a vlan, and apply a policy-map and set dscp 40 on
> egress of that vlan
> 3560 in uplinked in 7609
> in 3560 i can see the "marked" packets, and i have matches on the dscp
> set earlier (sh mls qos int xx stat).
> the problem is: when i apply the srr-queue in 3560 on egress (towards
> the test port), it does not work.
> if i enable mls qos on 3560, i cannot match anymore the dscp 40 from  
> the
> 7609
>
> is it normal? do i have to apply the qos stuff (point1) on all  
> switches
> i want qos on? i mean, i cannot set dscp in one "core" device and use
> that in the whole network ?
>
>
> thanks