VG200

mlouis · ‎10-29-2008

Today I ran into an issue with DSCP marking on a VG200 gateway. I have the gateway plugged into a 3750 switch. When i do a show mls qos int x/x stats command i see the inbound DSCP values incrementing in the 40-44 block (see below). This device is being used solely for SCCP Registered DSP for hardware conferencing. It looks like its marking its RTP media packets with a Precedence 5 value. Was this the case back in the day with this series of gateways?

AL_3750-Cluster24_2#show mls qos int gigabitEthernet 1/0/14 statistics

igabitEthernet1/0/14

dscp: incoming

------------------------------

0 - 4 : 23 0 0 0 0

5 - 9 : 0 0 0 0 0

10 - 14 : 0 0 0 0 0

15 - 19 : 0 0 0 0 0

20 - 24 : 0 0 0 0 0

25 - 29 : 0 0 0 0 0

30 - 34 : 0 0 0 0 0

35 - 39 : 0 0 0 0 0

40 - 44 : 13410 0 0 0 0

45 - 49 : 0 0 0 174 0

50 - 54 : 0 0 0 0 0

55 - 59 : 0 0 0 0 0

60 - 64 : 0 0 0 0

ivillegas · ‎11-04-2008

Issue the command several times to determine if the counter is incrementing. In case of undersized frames, it is only a cosmetic error and does not affect the operation of your switch or network.

You will not see the packets incrementing on the ingress side, if the marking is done after the packet has hit the interface. So, you would want to run 'show mls qos interface statistics' on the outbound interface, looking for the hits on the respective counters.

Configuring QoS:

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_20_se/configuration/guide/swqos.html