Why isn't tcpdump working?

  • 4 January 2016
  • 2 replies

Taken from a Cumulus support engineer's response:

"tcpdump will only show packets that are directed to or from the switch CPU. It will not show packets that are forwarded by the switch."

2 replies

if front port has strict 1:1 kernel port mapping ( and hopefully when pkt dma into kernel, linux know where it came from as well )

how about cumulus sample(sflow?) the packet from the data plane, when user try to tcpdump( cl-tdpcump ) a front panel port?
Thanks for bringing that up. It's definitely something we could consider and I'll bring it up internally. However, it's not implemented today.