Forum Discussion

neeeewbie's avatar
Mar 02, 2022

why f5 send reply packet when client tried telnet:80


Hi guys I need your help ! 


why f5's send reply(syn-ack) packet when client tried telnet:80?

but f5 does not have this ip

why f5 send reply ?? 

thank you


1 Reply

  • Hello,

    Without extract of your configuraiton, it's hard to spot the exact reason.

    Anyhow, the BigIP is a default deny device, so if there is syn ack, it mean you match something and you are not in the default behavior : maybe there is a virtual server listening on any ip ( or a subnet that match the trafic, as described in this article :