TCP connection limit got exceeded.

[Waseem Azhar <wa...@gmail.com>]

Hi,

I stumbled across a problem where my server stop responding to new http
connections. After inpecting logs if found an error message in tomcat logs
[SEVERE: Protocol handler pause failed java.net.SocketException: Network is
unreachable]. I did some investigation on my linux server logs and found
that there was simultaneous TCP connection limit (512) which got exceeded.
This is third time in a week I encountered this problem. Everytime I have to
restart my server machine.

I am using Tomcat 5, java 5.0, on linux machine (Fedora 5) . In addition to
that I am using HSQLDB (embeded in my web application). I am not gonna blame
tomcat for this. I believe there is something wrong with my In-Memory
database(which sarted as client/server mode ) when web-app starts. I have 2
applications deployed under tomcat, app A contains HSQLDB exposed at
a socket, app B connect to HSQLDB throgh tcp connection.

I want to spot the area where my tcp connections got open and not close. Any
suggestion? Any profiling tool who could help me ?

Thanks,
-Azhar