Topic: RAID 1 for backups

[Dub Dublin]

I'm looking at setting up an SME server for a small business, and I need to know if the following is do-able:

I would like to be able to use the RAID1 mirroring as a backup mechanism.  This involves turning it on and off (since of course, both copies get nuked if you accidentally delete a file while the mirror is live...)

The idea is that normally everything would run from one disk, but that periodically, the RAID1 mirror would be turned on allowing the disks to sync, and then the mirror would be broken again until the next backup.  (Of course, there also needs to be some way to tell it to rebuild the original mirror from the copy in case a "restore" is needed.  This is especially handy with removable disk drive sleds - since disks are now considerably cheaper than tape derives and cartridges, this is a very cost-effective backup solution.  (I prefer the mirror to the cruder tactic of just dd'ing one disk to the other, since the mirror makes disk consistency a surer thing, catching writes that happen after the copy has begun.)

Is there any way to do this in SME?

[Robert Boerner]

I have had a similar idea to what you propose, but it requires additional (although not too expensive) hardware.

Check out http://www.arcoide.com

They have a product called RaidCase that puts a hardware RAID1 board and two removable drive bays in 2 5 1/4 bays on the front of a PC case. This solution is OS independant and works transparently.

One of the things they recommend is a three drive rotation. i.e.

Start with two drives mirrored.

Each night, take out on drive and replace it with a third. The mirror will rebuild automatically. The drive you just took out is the backup. It can even be put into a new PC and work by itself, beacause it is a pure mirror.

Repeat each day.

FYI, I haven't tried this yet, but other people in the forum have said they used the hardware and it worked well. I am trying to get a hold of a unit myself. YMMV.