For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

neeeewbie's avatar
neeeewbie
Icon for MVP rankMVP
Sep 26, 2019

No traffic flowing when running tcpdump

Hello!!!

I need your help!

 

When setting interface mirror, I want to check the traffic to the mirror port. When using tcpdump -nei 1.1, no traffic flows to the mirror port. If you turn off tcpdump, traffic flows.

 

If you know the cause please let me know.

 

dest mirror port: 1.1 // mirrored port: 1.2, 1.3

 

Thank you.

application delivery
BIG-IP
operations

5 Replies

    • neeeewbie's avatar
      neeeewbie
      Icon for MVP rankMVP
      Oct 15, 2019

      Thanks!

      How do I check a packet without using the tcpdump command?

      • Anjuli_Lam's avatar
        Anjuli_Lam
        Icon for Employee rankEmployee
        Oct 23, 2019

        You should use an external capture device attached to the network interface to analyze (sniff) traffic that is mirrored to the interface. Hope that helps!

  • Rodrigo_Albuque's avatar
    Rodrigo_Albuque
    Icon for Cirrocumulus rankCirrocumulus
    Oct 14, 2019

    Are you trying to capture on the Standby? If this is L7 mirroring then try tcpdump on the same interface you'd receive external traffic if the box were Active.

    • neeeewbie's avatar
      neeeewbie
      Icon for MVP rankMVP
      Oct 24, 2019

      yes, F5 team release new note relate to this situaltion