Network is unreachable

[sacthivel.C]

Dear all,
I am using server which is loaded with rhl 9.0 (Dual LAN card).For the last 5 days intermittently the server is not pinging with the lease Line router and it is showing "Network is unreachable" error.
But when I restart the server it starts working.
This server is configured as our external mail server as well as our company's web server.

So pls help us to solve this issue.

Thanks in advance....

regards,
C.sacthivel

[Steven E. Protter]

Shalom,

See /var/log/messages at the time it happens.

It could be a bad NIC card, cable or switch port.

SEP

[sacthivel.C]

Dear Steven,
As you said i checked the messages log files and found that the network service get restarted automatically and after that only it starts giving the network is unreachable error.Also i am getting the neighbour table overflow error.(See my previous thread--->
http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1315142)
After spending sometime with my server i found that lot's of files starting with smtp and ems starts creating in the /tmp directory and after some time the server losses it's external connectivity.
I want to share some other things also.This server is also configured with IMSS(trend micro) software and the temporay files are created by this IMSS software only.(got from the users of that files).

Currently i am removing this files manually.I know this is not the solution.
So pls help me to solve this problem.

I am ready to share the details whatever you need regarding my server.

Thanks in advance.

Regards,
C.Sacthivel