mlq qos vlan-based Q?

Hello,

one question about mls qos on 3560, just to make sure that I've understood.
Diagram:

R1-----------------------SW1-----------trunk-----------------SW2---------------R2
R3-----------------------SW1-----------trunk-----------------SW2---------------R4

R1 and R2 are in VLAN 12, R3 and R4 are in VLAN 34. SW1 is routing
between VLANs via SVI interfaces configured for each VLAN.
Traffic in VLAN 12 should be mapped with ip prec 3, and traffic from
VLAN 34 with ip prec 4.
On SW1 I configured policy-map under interface vlan 12 (inbound) which
should mark packets according to task. Same thing for interface vlan
34. On the same switch I put mls qos vlan-based on trunk ports.
When I ping from R1 to R2 packets are NOT marked. When I ping from R2
to R1, packets are marked correctly.
Is the reason for that mls qos vlan-based command under trunk
interface? I mean, does it work only when traffic is going INBOUND
into physical interface? Actual marking is done on physical int or on
SVI int? Obviously interVLAN traffic is coming IN SVI interface on
SW1, but traffic still isn't marked with correct ip prec value.
Thanks.

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Received on Tue Feb 02 2010 - 19:05:29 ART