Wireshark · Wireshark-users: [Wireshark-users] Odd tcp establishment sequence?

[Mohamed Lrhazi <lrhazi@xxxxxxxxx>]

Hello,

am trying to debug why often times, my ssh client timeout trying to establish connection to an ssh server (F5 device)... 

Often times, I see a SYN sent twice, then server responding with an ACK, then an SYN/ACK, then my client sends RST.

Other times, I see several SYN re-transmits, then ACK response, then SYN/ACK, then ACK from client and connection getting established!

This is all not very normal, right? especially the ACK in response to a SYN? that should cause clients to fail to continue establishing a connection, right?

Thanks a lot for your input, I know this is not wireshark issue!

Mohamed,

Attachment: f5-aom-odd-tcp-connection.PNG
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Attachment: f5-aom-failed-tcp-connection.PNG
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