On Saturday 23 September 2006 18:53, Ian Cheong wrote: > We had this discussion on failure tolerant clusters a while back - at > the time, nobody owned up to having one.
And it might be expensive overkill. While I am constantly experimenting with automatic failover recovery through a replicated server, so far our "tried and proven" simple & cheap solution has not disappointed us: 1.) All relevant software and data is hosted on a single computer, the "server". 2.) All people interacting with that software / data are connected via "clients" - either thin or fat, but only requirement to a client computer is the ability to run the X protocol and ssh. Meaning I can take a brand new laptop with a blnk harddisk, boot from a Knoppix CD, and can start working as soon as the CD has booted 3.) The server does not depend on any internal harddisks - it is connected via eSATA to an external RAID cage. The hard disks in the RAID cageare hot swappable. Apart from sending an email to the administrator(s), the RAID cage emits an audible alarm and displays error messages on a LED screen if one harddisk fails 4.) All our "client" computers are equipped with eSATA connectors and can act as instant drop-in servers in case the server fails 5.) We have a second spare RAID cage in case the RAID cage fails 6.) Offsite backup via rsync of server to hospital and my house twice daily (in case the surgery burns down or some such) 7.) all computers are connected to good UPS 8.) spares for network cables, keyboards, mice, switches and ADSL modem on site + notebook that can replace either server or client. If you do the numbers you will see that our solution is actually CHEAPER than having fully installed client computers for everybody, it requires only a fraction of the administrative effort, and yet it is far more failproof. Horst _______________________________________________ Gpcg_talk mailing list [email protected] http://ozdocit.org/cgi-bin/mailman/listinfo/gpcg_talk
