[c-nsp] DSCP and Queue counters on 7600s

[James Bensley]

Hi All,

Got some 7600s with RSP720-3CXL-10G and LAN cards (CFC, no DFCs) and
I'm "trying" to run QoS on them.

Does anyone know of a command to show the number of packets that
entered each queue/show some queue counters?


Full background:

This old C-NSP thread suggests the ports must in "mls qos trust cos"
if you want to use queuing and congestion avoidance on LAN cards
(unless using WS-X6708-10G cards which can queue based on DSCP), which
also ties up with Cisco's website:
http://www.gossamer-threads.com/lists/cisco/nsp/142328
http://www.cisco.com/c/en/us/td/docs/routers/7600/ios/15S/configuration/guide/7600_15_0s_book/qos.html#21195

So the dilemma seems to be that I can put the ports in "mls qos trust
cos" mode and have queuing based on the CoS value (which we don’t use)
but I can use the DSCP to CoS maps so the router will derive a CoS
value from the DSCP value (which we do use) and then queue based on
that. Or I can put the port into “mls qos trust dscp” mode which means
nothing happens really, as the LAN cards don’t support queuing based
on DSCP values.

Speaking with TAC the engineer is saying that Cisco page is a bit
ambiguous and I can put all my ports into “mls qos trust dscp” mode
and queue based on DSCP value (it will use the DSCP to CoS map to
derive the CoS value). OK so if I want to test this how can I check
how many packets are going into each queue?

I've neve seen such a command on the 7600s (I don't think there is one
for the LAN cards). Does anyone know if we can look deeper perhaps
into the port ASICs?

Cheers,
James.