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QOS tagging on 6509 not working


for our Lync VOIP System we need to tag traffic comming from Macbooks with the dscp value af31(dscp 26), because they do not use qos like Windows machines.

I did an test on some old 3550 in our Lab and i was able to tag traffic to specific ports, when they are untagged.

Lync is using these ports:


20000 - 20039

49152  - 57500


Our branch office switch:


Catalyst 6000 supervisor 2 (Active)    WS-X6K-SUP2-2GE

1 Policy Feature Card 2       WS-F6K-PFC2
1 Cat6k MSFC 2 daughterboard  WS-F6K-MSFC2

ROM: System Bootstrap, Version 12.2(17r)S1, RELEASE SOFTWARE (fc1)
BOOTLDR: c6sup2_rp Software (c6sup2_rp-PK2S-M), Version 12.1(26)E3, RELEASE SOFTWARE (fc1)



   mls qos
   mls qos rewrite ip dscp
 ip access-list extended acl_lync_qos_mac
 permit udp any any range 20000 20039
 permit udp any any range 49152 57500
class-map match-all cm_lync_qos_mac
 match access-group name acl_lync_qos_mac
class-map match-all cm_lync_default
 match ip dscp af31
 policy-map pm_lync_qos_mac
 class cm_lync_qos_mac
  set ip dscp af31
 class cm_lync_default
 trust dscp
  interface fa4/11 (which is the interface from our firewall, its only forwarding data to our mpls)

 service-policy input pm_lync_qos_mac



However the dscp value is not set, like on the packets comming from the other branches(with 3550 for instead).

After some hours of research i was unable to find an solution, the only command which was needed on the 3550 and is not working on the 6509 is

"mls qos rewrite ip dscp".


Has anybody an solution for this problem? Are there any hard- or software related limitations?




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