10:53:04.042608 IP 172.17.2.12.42654 > 172.17.2.6.6000: Flags [FPU], seq 3891587770, win 1024, urg 0, length 0 10:53:04.045939 IP 172.17.2.6.6000 > 172.17.2.12.42654: Flags [R.], seq 0, ack 3891587770, win 0, length 0 Between these two packets I am looking for the set flags and what they mean... What I am assuming is the flags are FPU and R as the packets state, but I am not familiar with these flags and cannot seem to find an answer to what they are anywhere else. Would anyone know what flags they are? asked 22 Mar '14, 13:09  Cashmen edited 22 Mar '14, 14:34  Kurt Knochner ♦ |
One Answer:
What you are showing is the output of tcpdump and the flags are documented in the man page of tcpdump. In short (from the man page):
For a better understanding of the flags, please visit online resources like the following, and many others.
So, what you are seeing is:
So, one side is closing the connection with a FIN (plus other flags) and the other side 'answers' with a RESET. Why it happens in that way can only be answered by looking at the applications and operating systems in use. Regards answered 22 Mar '14, 14:03 Kurt Knochner ♦ edited 22 Mar '14, 14:17 |
