I’m currently looking to upgrade from OpenMediaVault and have been looking a TrueNAS Scale as a possible way forward. As a complete TrueNAS noob, I’ve got some open questions about the capability of the system:
Is it possible to have the system to use individual disks instead of a pool/raid setup?
Can you add drives, which already contain data, without having to wipe the drive clean?
In OMV I’m using snapRAID to add a parity drive for my two data drives to recover data in case of a drive failure and proctection against bitrot. Is it possible to achieve that in TrueNAS scale without using an array?
Can you have individual HDDs spin-down and stay silent, when accessing data from an other drive?
Yes, although in that case you have a pool with a single vdev of a single drive.
If the drive contains a ZFS pool you can import it keeping your data. If it doesn’t, no. The only supported file system for storage is ZFS.
No. Redundancy is provided by ZFS per vdev on a block level. RAIDZn and mirroring are completely oblivious of files. Files and datasets are an abstraction layer on top of a redundant or non-redundant pool.
What do you mean? You do not need hardware RAID. You would want more than one disk per vdev/pool. ZFS does not work like Unraid/SnapRAID/OMV.
If your existing data is on a ZFS pool, you could export the pool from the existing system and import on TrueNAS without losing data. If the existing data is not on a ZFS pool, to use them in a new ZFS pool you will need to wipe them.
What do you mean ‘without using an array’? You will want multiple disks to create a vdev and pool from. ZFS handles bitrot better than SnapRAID, because it detects and corrects it automatically.
You can force ZFS to allow disks to spin down, but the entire pool is spun down – not individual disks.
If you want data stored on individual disks instead of distributed, you will probably want to stick with OMV, Unraid, or similar.
It doesn’t seem like you’ve done any reading about what ZFS is or how it works, so here’s a good introduction:
The whole point of ZFS is to provide protected storage for valuable data - if you don’t value your data enough to provide redundancy, then perhaps ZFS (and hence TrueNAS) is overkill for your needs and you would be better of sticking with OMV.
Yes - if they are already using ZFS. But if not, then No.
Not sure what SnapRAID is but ZFS does software RAID and hardware RAID is not supported.
ZFS supports detection of bitrot on all pools - but it provides correction of bitrot only with redundant vDevs / pools.
Spindown times are defined individually by disk, but disks are accessed by pools. But…
