Hello everybody,
we are running a pair of c9500-32C in stack wise virtutal mode and are experiencing some problems regarding multicast forwarding.
Right now, we have:
IP Multicast Statistics
713 routes using 1157112 bytes of memory
323 groups, 1.20 average sources per group
multicast running.
The topology is:
sender - c9300 - Po48 - C9500-48Y4C #1 - Po 126 - c9500-32 #1 - Po52 - 3rd party Switch - receiver
- Po48 - C9500-48Y4C #2 - Po 126 - c9500-32 #1 - Po52 -
I aware of at least one stream, which isn't forwarded.
I've verified via ERSPAN, that the stream is forwarded to the c9500-32C router pair and that an IGMP v2 join is also received by the router pair. But the traffic is not forwarded to the receiver.
I can see, that there is lots of traffic dropped:
Router#sh controllers cpu-interface
queue retrieved dropped invalid hol-block
-------------------------------------------------------------------------
Routing Protocol 8525620 0 0 0
L2 Protocol 22755134 0 0 0
sw forwarding 300029627 207673969 0 0
This could have something in common with CoPP:
Router#show plat hardware fed switch active qos queue stats internal cpu policer | ex qq| 0|qq
CPU Queue Statistics
============================================================================================
(default) (set) Queue Queue
QId PlcIdx Queue Name Enabled Rate Rate Drop(Bytes) Drop(Frames)
--------------------------------------------------------------------------------------------
19 10 RPF Failed Yes 250 250 2384770 1647
30 9 MCAST Data Yes 500 1000 124503376152755 85287664246
* NOTE: CPU queue policer rates are configured to the closest hardware supported value
CPU Queue Policer Statistics
====================================================================
Policer Policer Accept Policer Accept Policer Drop Policer Drop
Index Bytes Frames Bytes Frames
-------------------------------------------------------------------
9 332283058544 225410532 124503376195629 85287664275
10 119731216 226694 2384770 1647
How can I see in detail, what packets are dropped and why? Why is multicast traffic even punted to the CPU?
Best regards,
Sebastian
