our server suffered a serious connection timeout problem, so we track tcp connection with tcptrack
we found out that, if the client started to connect to the server, tcptrack shows the connection, but in SYN_SENT status, and
netstat -nat shows nothing. (tcptrack & netstat all runs on the server)
- does this mean the syn request reached the server? and no syn/ack was sent back?
- why the tcptrack could report this connection but netstat could not?
- what could be the problem that a general apache could not establish a connection with the client?
i did a bench test using
ab in the same intranet, to the specified NIC, it handled 10000 concurrent connection and 400000 requests ok
ps: this doesn't happen every time, but did happened a lot
pps: is there any good tools to trace where the tcp connection was lost?