This is the situation. I am presently running the email program communigate pro on a solaris 8 sparc box. What I want to do is setup another server running the exact same thing so that if one server goes down the other one will automatically start up. Basically I want to store the data in a central storage RAID 5. Now I was wondering if anyone had any suggestions on how to acomplish this. Is there a raid 5 box that would do this job and how would i setup a server to automatically switch on and resume the duties of a failed email server.

One possibility to get near this at very little cost is to use disk sets. In hardware you will need at least two SCSI chains strung between 2 sparcs. Each sparc has a different SCSI initiator ID eg 6 and 7 No disk uses either of these IDs. For software you will need solstice volume manager (SVM) to create a metadevice on these disks. In disk sets at any time only one sparc has ownership of the disks. Only one sparc can. For your application of course only one sparc needs access to the disks However you will need to do some scripting! The metaset command can tell either sparc whether it is the owner of the disk set or not. Using this result in scripts the sparc chooses whether to start up an extra IP address associated with the mail service and start the mail server applications or conversely to shut down the mail service IP and shut down the mail server services and let the other sparc do the job. As a minimum you will need to write scripts S99xxx and K05xxx in /etc/rc2.d and /etc/rc3.d (which are hard links to just one script in /etc/init.d) with metaset -r to release the disk set on shut down "stop" and metaset -t to take ownership on start up "start" (or at least try if the other sparc is out of action) Also you will need to have a cron job to watch for the server sparc stopping unexpectedly and doing a forced take of the disk sets if necessary. You must ensure the service only runs on a sparc if it owns the disk set. Both sparcs can't have the mailserver IP address live at the same time. Not an instant out of the box solution - for that you need to buy 3rd party solutions. But metaset and SVM are free with solaris now. How good or otherwise a solution using disk sets and scripts is depends on the quality and complexity of the scripts you write. References see man page on metaset to get started

what I have decided to do is to go with a sun StorEdge 3310 SCSI Array running raid 5 and storing my email accounts and the two sparc boxes, each with identical setups so that if one goes down the other one can be turned on and take over the duties until the other one can be resolved. As for coping over the files from one server to the other, what would be the best way to accomplish this.