Connection to mysql server in SYN_SENT

Posted by Sunil on Server Fault See other posts from Server Fault or by Sunil
Published on 2012-04-07T12:35:22Z Indexed on 2012/04/07 17:34 UTC
Read the original article Hit count: 299

Filed under:

mysql

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tcp

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rhel5

We are facing a strange problem from last few days between our application server and database server(Mysql): connection to database server from application server hangs in SYN_SENT state and after that we are not able to make any connection to database server on mysql port(3306). When we checked the netstat output on database server its in SYN_RECV state.

What I can figure out is mysql server is receiving the SYN request and responding also and its not reaching to the client hence SYN_RECV at server side and SYN_SENT at client side. I think SYN_SENT state should go after some time and because of this other db connection attempts to same server should not hang.

Does anybody have any idea how can we resolve this issue?

Out setup details :

Application server: RHEL 5.4, kernel-release = 2.6.18-164.el5, x86_64

Database server: Mysql Version : 5.1.49 RHEL 5.4, kernel-release = 2.6.18-164.el5, x86_64

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