On 10/17/06, Sherwyn Greene wrote:
Yes, I would like to have a shared storage setup, the question is can I do it from the scsi cards I have & if so what other equipment I need to have this setup.
This is actually a fairly complicated question-- more than a mere CentOS mailing list can likely answer to the level of detail you're going to need. If you have not set up shared storage before, you may want to find a local consultant to help out.
With that said, yes, you can use your existing SCSI cards provided you find the right kind of storage and your SCSI cards are "differential" SCSI (e.g. low-voltage differential). There are tons of vendors, large and small, that would be eager to take your money and sell you a disk array that would work. I would suggest the following requirements to jump-start your search: + dual SCSI channels from each host compatible with your existing cards - so if one card dies you can keep working + RAID-5 in hardware + battery-backed cache on the RAID controller - so you can survive a power loss with minimal data lost - you probably want a battery that will last at least 7 days, perhaps longer + hot-swap disks + 24x7 support including on-site hardware replacement - if you can get by with less, you probably don't need a cluster... + [optional] automatic hot spare disks (these take over for a failed disk until you get it replaced) - the need for these depends on how quickly you're likely to replace a dead disk as well as how many disks you have total
EMC and HP/Compaq both make excellent, if expensive, storage. This might be a good place to start your vendor search since this will set an upper limit on how much it's likely to cost.
Again-- seek competent local help. I don't think you can learn enough about what to do from this mailing list. ;-)
-- Steve