[CentOS] Server closing all the ports after inactivity Could not connect to webserver

Hi All
I am running Centos -4.4 final with all the updates 
My webserver stop responding after about half an hour od inactivity.I just 
gets a timeout message. When I try to refresh the page 3-4 times it start 
active again.
Infact all the ports on the server are closed  during the inactive period even 
though I have ssh,ftp and http enabled on it. When the server is responding I 
can see (with a port scan)the ports are open.
I tried disabling the firewall(on the centos server) altogether because the 
server sits behind another firewall.
If I do a restart of the httpd or do any other network related stuff on the 
server it opens the ports again.
Any help is appreciated
Regards
Anil
-- 
Most operating systems were developed for commercial or technical motives, 
but GNU was developed for the sake of giving users the freedom to cooperate in 
a community. And if users don't know this, they will be in danger of losing 
their freedom.
--Richard Stallman
Public Key
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Anil at cuty
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