Hi, We have a number of VC units running on 3750's and 3560's using the following QoS policy:
class-map match-all Video_Packets
match access-group name Video_Packets
set dscp af31
ip access-list extended Video_Packets
permit udp any range 17000 17310 any range 17000 17310
permit udp any range 17000 17310 any range 49000 49310
permit udp any range 49000 49310 any range 17000 17310
permit tcp any range 1700 1750 any range 3230 3235
permit tcp any range 3230 3235 any range 1700 1750
permit tcp any range 1700 1750 any gt 1024
permit tcp any gt 1024 any range 1700 1750
permit udp any host 10.xxx.xxx.xxx
We pay our telco to provide QoS over our WAN circuits but have a doubt that they are actually tagging the packets due to the quality we are experiencing.
Using Wireshark/Ethereal can anyone tell me what to look for (If I carry out a trace) to see if the packets are being marked/tagged?
Any help appreciated.
What do you see when you do "sh policy-map int xxx" and "sh access-list"? Any hits?
What kind of problem that you're experiencing?
Service-policy input: Video_Conf
Class-map: Video_Packets (match-all)
0 packets, 0 bytes
offered rate 0 bps, drop rate 0 bps
Match: access-group name Video_Packets
Class-map: class-default (match-any)
0 packets, 0 bytes
rate 0 bps
The Polycom units show packet loss and the picture is always pixelating and refreshing.
It sporadically freezes for a split second then goes out of focus.
The switch port shows no errors whatsoever.
Hope this helps?
Can you also post the router config where the 3750/3560 is connected?
A couple of things that you can try:
1. Change "class-map match-all Video_Packets" to "class-map match-any Viideo_Packets" so that it'll match any parameter in your access-list.
2. Take a look at your Polycom unit. I may be set at "IP Precedence 4" instead of "AF31". If so, change it in your policy-map.
3. Verify that the port speed and duplex are set to "auto" where the Polycom unit is connected in your switch port.
4. Take a look at this document: http://www.cisco.com/en/US/tech/tk1077/technologies_configuration_example09186a0080111c1b.shtml
"Using Wireshark/Ethereal can anyone tell me what to look for (If I carry out a trace) to see if the packets are being marked/tagged?"
Look for either a DSCP or IP Precedence decode in the IP packets carrying the video traffic. Ideally, off the link coming off the WAN.
If your Telco tags the traffic, why are you setting DSCP?
Besides tagging, has the Telco committed to any SLA with regards to bandwidth, latency, jitter and/or loss, for your video traffic?
Who manages the WAN routers and what type of WAN circuits are being used?