Good forms of Backup

A RAID isn't necessary for backups if what you're backing up is available elsewhere. For instance, if you're making a Time Machine backup of your system, a Drobo may be overkill. Just one physical drive would be sufficient assuming it had the space. The thought process is that it is highly unlikely that both your original (computer) and backup (external drive) are destroyed at the same time. When one bites the dust, you'll have time to procure a replacement and restore/recreate the backup.

RAID setups are encouraged for 3 reasons:
1) To improve throughput by channeling drives.
2) To build a volume larger than the individual drives (>2TB)
3) To provide a failsafe drive (or drives) to keep data online in the event of a failure.

RAID is not a backup. I run a ReadyNAS in RAID5, and a OpenNAS in RAID1. Both have a separate external drive for backups.
If all your data exists on your system already, RAID is overkill.
If the RAID is where the only copy of data will be, you should have a backup for the RAID too.

 

There are many threads on the Drobo packed with good info. Basically it's good but when it fails your HB are unusable unless you buy a new Drobo (it's not standard Raid)

Edit : here some links :-D
http://forums.macrumors.com/showthread.php?t=809088&highlight=drobo
http://forums.macrumors.com/showthread.php?t=803368&highlight=drobo
http://forums.macrumors.com/showthread.php?t=602549&highlight=drobo
http://forums.macrumors.com/showthread.php?t=790471&highlight=drobo
http://forums.macrumors.com/showthread.php?t=763284&highlight=drobo

 

i was considering a DROBO as well, until I realized its actually a big external scalable storage device.

For backup I went with two external firewire drives, and Superduper software. One is connected to the iMac and the other offsite. Every two weeks or so i just switch the drives. If and when I get close to filling them I'll buy bigger drives.

Oh the dlink in my signature , is for my windows workstations...

 

Do you need to have it available to multiple systems?

If not, you can just get an eSATA card, and a Port Multiplier enclosure. Drivers for the card usually posess some RAID settings, and JBOD (concatenation; all the drives connect together appearing as a single drive to the system) would work quite well if you need one large space. Otherwise, just split it up (directory/s 1 -x to disk A,... type of thing).

RAID by itself is NOT a backup. But you can use a RAID as a backup for another RAID. Just don't connect them via the RAID settings in any way. You use backup software to handle the data (schedule and locations).

The above would apply to you as well.

Its not an expensive way to go either. Cheaper than DROBO I think, as you can get a card for $25USD (driver support only for OS X, but that's all you need) and an enclosure can be had for $225 - 250USD (holds 4x drives). Larger are available, and a 2 port card can run up to 10x drives (1 eSATA per 5x disks).

 

I've got two dual-bay Icy Dock Firewire enclosures. These will do RAID 0, 1, BIG and JBOD. I like them because they're screwless and easy to swap out drives. The internal fan speed is adjustable, which is also nice.

 

The enclosures