I'd like more ellaboration on the technical side. Not literally how to do the same and what commands to use, but more in the line of how are the ZFS pools configured, or if Garage is opinionated and configures it all by itself. Are there mirrors in there? Or it's just individual pools that sync from some disks to others?
I have 2 USB disks and want to make a cheapo NAS but I always doubt between making a ZFS mirror, making 2 independent pools and use one to backup the other, or just go the alternate route and use SnapRAID and then be able to mix more older HDDs for maximum usage of the hardware I already own.
> doubt between making a ZFS mirror, making 2 independent pools
You will gain protection agains bit-rot and self-healing (via scrubs) with a mirror. Also faster reads.
> mix more older HDDs
You can do this with ZFS too! As long as you have two HDDs of the same size (or similar size, as to not loose too much to unused space), you can also add them as a mirrored zdev to your existing pool (or make an new one for backups as you wrote). Only the two disks in a mirror need to be of similar size, not all disks in a pool.
My understanding is that Garage is not opinionated and could easily have worked without ZFS. I installed ZFS in Ubuntu, and then later installed Garage.
As for the ZFS setup, I kept it simple and did RAID5/raidz1. I'm no expert in that, and have been starting to think about it again as the pool approaches 33% full.
I saw this comment in another thread here that sounded interesting as well by magicalhippo: "I've been using ZFS for quite a while, and I had a realization some time ago that for a lot of data, I could tolerate a few hours worth of loss. So instead of a mirror, I've set up two separate one-disk pools, with automatic snapshots of the primary pool every few hours, which are then zfs send/recv to the other pool."
This caught my attention as it matches my usecase well. My original idea was that RAID5 would be good incase a HD fails, and that I would replicate the setup at another location, but the overall costs (~$1k USD) are enough that I haven't done that yet.
If you know where to look/are a little lucky, you can get an adequate RAID5 going for like $500-800 depending on the storage you need. I grabbed a QNAP 4 bay (no SSD caching) and 4x refurbished enterprise HDD's (14tb/ea) for just under $700 all-in last november if memory serves. Pretty reasonable for a 42tb RAID5 IMO.