SW for Failover system

[Padiyath Sreekumaran]

Hello,
  Perhaps Iam at wrong FAQ list. I have 2 machines, say, a server and a
slave machine.If server goes down because of some reasons slave should 
comes in operation.Has any one got experience with such a configuration?
Is there any SW available?(preferred free one if possible). Is there any
docs available on the net? We need such configurations for our different
servers(webserver, database server etc.) 

I will appreciate very much your suggestions.

Thanks in advance and with regards,
     Kumar 
   
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Padiyath Sreekumar       |   Tel: +41.56.310.3643
Paul Scherrer Institut   |   email: kumar.padiyath at psi.ch
AIT                      |   Office: WHGA/U132 
WHGA/U132                |   Fax: +41.56.310.3649
CH-5232 Villigen PSI     | 
Switzerland              |
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