Lewis, Don wrote:
I am trying to use Wireshark to resolve a QoS issue. We have a polycom
video conference camera on our site that is setting up a session with a
remote polycom. Our ISP says they are not seeing any packets marked
appropriately. Their evidence is NETFLOW reports collected from their
edge router located on campus.
Should I be able to set up a remote span session (all Cisco hardware)
and see the QoS in the packet’s Differentiated Services Field?
My monitor session look something like this:
Switch 1 (site with our Polycom)
Monitor sess 1 source inter fast x/x both
Monitor sess 1 dest remote vlan 400
Switch 2 (my office)
Monitor sess 1 source remote vlan 400
Monitor sess 1 dest inter fast x/x
I have been looking for a sample QoS trace just to see what it would
look like but could not find one.
You should capture on the *egress* port from switch 1. Don't capture
the whole vlan, just capture the polycom.
You can also capture it at your office as it leaves for the ISP.
There's no special config for QoS. It just uses 6 bits of the ToS field
to come up with the DSCP code points.
I didn't think netflow collect DSCP code points, but I could be wrong.
Anyway, if you capture it, just make sure the polycom traffic's code
points correct (correct == whatever is defined on the router to be
treated as high priority traffic)
--
Thanks,
Hansang
