I have an RH 7.1 server runnning DNS, SMTP, POP and Webmail.
I have a problem of connections timing out.

Running netstat -n|grep SYN_RECV shows a couple of connections waiting.

I want to increase the maximum number of sockets to about 1024. I understand the Linux default is 128.

I have read a few documents on this but I have not come across a clear one. They simply point to SOMAXCONN in /usr/include/linux/socket.h

If I change this value to whatever figure I want do I need to recompile the kernel or do I simply reboot the box for the new value to work.

Is there a command I can use to see the current set value.

I would look at increasing the #/ephemeral ports on your system before doing anything else:

http://support.zeus.com/print.cgi/fa...ail_ports.html