CentOS

I have installed a software based on Fire Alarm graphics under Centos 4.6. The problem is sometimes it shows communication lost. The program is started on init 4.
THe specification are given below
HP Compaq Elite 8200 convertible mini tower
Serial port Nos. 2 (One is inbuilt)
Ethernet Cards-2( One is inbuilt and other one is Linksys).The problem is after one day or some times more, the main ethernet card shows communication lost. But the ping is ok. Please give me a valuable reply.

Welcome to the CentOS fora. Please see the recommended reading for new users linked in my signature, and [url=http://www.centos.org/modules/newbb/viewtopic.php?topic_id=28723&forum=54]provide more information about your system[/url] by running "./getinfo.sh" and showing us the output file. I have not idea what "Fire Alarm graphics" is (Google turns up a lot of hits on fire alarm systems), nor what that has to do with network issues.

Please be aware that CentOS-4 has passed [url=https://www.centos.org/modules/newbb/viewtopic.php?topic_id=36132&forum=48]EOL (End Of Life)[/url] and is not supported. You should install a supported version as soon as possible. Meanwhile you should at least update to the latest packages in CentOS-4.9 plus subsequent errata with "yum update".