I’m using my old MacBook as a backup server and to feed it, I’ve purchased TerraMaster 4 Drive Bay and 2 x 12TB Seagate disks. I’m trying to decide do I just add these as independant disks? or Raid 0? I don’t need Raid 1, because this is backup only. If ever I lose a backup disk, I don’t stress and just start up again from scratch.
JBOD - no real configuration required, easier to add more disks
Raid 0 - faster performance, no need to decide which mac backs up to which drive
We have four macs in our family and they will backup every night, some will backup 30+ GB in single session. (The machines being backed up have 4TB, 2TB, and 2 x 1TB)
This means, I might need to be clever with the scheduling.
Use JBOD. You don’t need faster performance, and it will be more reliable. Splitting between the drives should be no problem since your four Macs will easily back up to a single drive if needed. I wouldn’t worry too much about scheduling – see how long a typical backup runs for each and then just spread out the times.
Agree with JBOD if you don’t care about losing all of your data in the event of a drive failure. The only reason to use RAID 0 is better performance.
But I’m with @geoffaire about RAID 1. If you don’t care about losing all of your backup data at any given time, I would question why you’re doing backups at all. I run a 4-drive array in RAID 5 for the same reason I’d suggest you using RAID 1. One drive can fail, and you still have your backups.
Since you have a 4-drive array, you could also consider adding two more 12 TB drives and running RAID 5. That way you’re not losing as much storage as RAID 1, but you still get single-drive failure redundancy.
If you want the “more storage” on the same volume, I would say “yes.” But you should be able to add another pair of disks as a second, separate volume.
Ah, I see. I was of the impression you had an enclosure that did the RAID for you, and that this was the primary backup for your machines. If this is “yet another backup of many,” I don’t see any reason you shouldn’t just do JBOD.
FWIW, I experimented with RAID 1 using macOS support, not external chassis or hardware.
I found it works, but barely. Fiddly configuration using macOS Disk Utility and easy to make a mistake as the UI isn’t that straightforward.
Testing unplugging one of the drives and rebooting the Mac to practice various recovery scenarios (can I re-mirror and which drive will macOS consider “good”) was too much white-knuckle cognitive overload for something I wouldn’t be doing very often.
I ended up buying two large external single drives and rotating them as backups.
I figured the reliability of a drive offline and completely air-gapped is easier and fine as an additional local backup to my other backups still in place.
I probably have exactly the same disk enclosure as you. I went with JBOD because when it comes to backups, simple is king and complexity is the enemy of happy recoveries.
I also back the whole thing up to Backblaze, but this is a place where I take as few chances as possible, and make my recovery process as simple as possible.
To put it another way, I would have a hard time imagining a backup system in which the risk of having a 400% increase in the probability of catastrophic failure doesn’t outweigh the utility of the system.