ASR9k Netflow and QOS order in the inbound direction
My customer match a issue that business traffics take IP6,7 flag, then the traffics auto mapping to EXP6,7 that cause control police congestion, and ISIS flapping due to BFD flap. So they want to check which traffics have incorrect flag by netflow, so need to check ording for netflow and QOS at input direction. I check some documents, nobody notice that, so the article will show test info, you can check if you need. Finaly test result: At ingress direction, packets will be cached first by netflow, then do other action in QOS.
Btw, due to auto mapping from TOS to EXP by range, e.g: TOS 192-223 will map to EXP6; TOS 223-255 will map to EXP7. So if we want to check the issue by netflow, suggest filter EXP data, as in my follow test, check by follow command:
RP/0/RSP1/CPU0:ASR9006-G#sh flow monitor test-mpls cache brief location 0/0/cpu0 | i 7-0 Fri Jan 8 04:57:39.604 UTC LDP 22.214.171.124/32 30000-7-0 40034-7-1 - - - - Te0/0/0/2 Te0/0/0/1 Fwd 3888 36 Egr 126.96.36.199 188.8.131.52 0xff icmp 0 2048