With 20 TB drives, I would have concerns about a drive failure during a rebuild. I suggest at least 3 drives and a config that can handle 2 failures.
Unless everything is replaceable.
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With 20 TB drives, I would have concerns about a drive failure during a rebuild. I suggest at least 3 drives and a config that can handle 2 failures.
Unless everything is replaceable.
Spot on.
Plan a little for growth, maybe a 5 drive unit with 12TB drives, with duplicate parity.
Optionally: Two 20 TB drives mirrored, cloud backup (e.g. Storj. io or another), perhaps another local 20TB drive that's a backup or a local replica.
Edit: any approach needs to include off-site backup, and that backup needs to be tested, at least quarterly.
At least get one more and set up a raid1 so each drive contains a copy of the data.
The downside is this limits your expandability as converting between raid levels is not easy and you don't get any additional space.
If you get 2 more drives you could go for a zfs1 or raid5 to get the extra space and a drive in case of a failure.
On a synology NAS you can use SHR-1 raid (which is basically raid 5) with just two disks. In pratice that acts like raid 1, but you can just add more drives and it will act like raid 5.
Not sure if other NAS have similar custom raids.
I would at least add two additional 20TB drives and put them into a raid 5. That gives you around 40TB of usuable space and you can have one disk failure.
I use zraid1 (kinda like raid5 but much better) in zfs with a stack of 18TB drives
Look into Mergerfs+Snapraid. I’ve recently started using this setup for my media drives and it works great. Mergerfs allows you to treat any mixture of drives as one giant pool, while snapraid allows you to define parity drives for that pool. However snapraid requires each parity drive to be as big as your largest data drive. But this is a flexible and economical setup if you already have disks
Unraid. Mix and match drive sizes. Its magic
But you only get the storage capacity of the smallest drive, right? So in a 5 drive RAID, if one drive is 1TB and the rest are 5TB, it's 1TBx5
It's been a while since I setup UnRAID, not sure if I remember right.
Kinda depends The parity has to be larger than your largest drive. but you can have it move data around between fast and slow drives as it is used. It can do pretty cool stuff with a few clicks. It amazes me every day.
Thanks for the suggestion. I will take a look.