MVPHello!!!
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.
EmployeeK65535212: Limitation of using the tcpdump utility on mirrored interfaces
MVPThanks!
How do I check a packet without using the tcpdump command?
EmployeeYou should use an external capture device attached to the network interface to analyze (sniff) traffic that is mirrored to the interface. Hope that helps!
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.
MVPyes, F5 team release new note relate to this situaltion
