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Uttam_Shrestha1's avatar
Uttam_Shrestha1
Icon for Nimbostratus rankNimbostratus
Nov 27, 2013

F5 LTM virtual server IP address:172.20.16.225 can get TCP request from 10.11.1.4, but not return TCP ACK

We are facing some issue on the F5 LTM: we have trace the network no issue as we can ping and trace on either network, but while checking the tcpdump which I have attached here a screen captured show...
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Kevin_Stewart's avatar
Kevin_Stewart
Icon for Employee rankEmployee
Nov 27, 2013

So you see a client at 10.11.1.4 initiate a TCP handshake to the self-IP of the F5 at 172.20.16.225, and you see the SYN packet arrive at the F5's interface, but then the F5 doesn't complete the handshake? Do you by chance have any port lockdowns applied to the self-IPs? Packet filter rules? Are you simply pinging or something else?