[nsp] 12.2(12a) & fe/dot1q/decef/mpls

[Tomas Daniska]

hi there,


we're experiencing lots of input drops when the 7500 receives a packet
on a dot1q subinterface that has to be switched on another subinterface
of the same fe port. the following are the conditions:

- 7500, 12.2(anything) with decef & mpls enabled
- egress interface is a vrf interface (the 7500 is a PE)
- fifo queueing

'sh int' vip reports the packets as ignored, rsp reports them as in-q
drops. 'sh int switching' shows them as route processor drops

if i turn off decef on the interface (no ip route-cache distributed)
everything works great. if i setup some other queueing (priority, cbwfq)
the drop rate decreases (about tenfold) but still occurs


this occurs even with minimum traffic loads (ones of kpps), drop rate is
about 5-10%. i can safely reproduce this with a simple mpls vpn scenario



has anyone experienced this, too?


thanks

--
 
Tomas Daniska
systems engineer
Tronet Computer Networks
Plynarenska 5, 829 75 Bratislava, Slovakia
tel: +421 2 58224111, fax: +421 2 58224199
 
A transistor protected by a fast-acting fuse will protect the fuse by
blowing first.