http server connectivity puzzle

Posted by jpmartins on Server Fault See other posts from Server Fault or by jpmartins
Published on 2010-01-29T17:09:46Z Indexed on 2010/04/09 8:03 UTC
Read the original article Hit count: 275

Filed under:

Troubleshooting

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network

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webserver

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ip

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availability

I have been seeing some strange connection issue in the production environment.

The setup has two IBM Http Server's (IHS) and a network IP load-balancer in front of them (round-robin).

One instance the system is working fine, the next requests stop arriving at the IHS. Telnet directly to port 80 of the IHS is established sucessfully, but connection to the port 80 through the IP of the load-balancer fails!

The puzzle comes next, the network admins say the load-balancer is working fine. When we finally reboot the IHS servers and request start flowing...

The situation happened three times the last month and no obvious pattern was found.

Any debug ideas?

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