brwainer

I was going to respond with “OpenZFS doesn’t have any option to remove a drive from a zvol, except to turn a mirror into a single disk”, but now that you’ve said this my response is “please show an example of the commands that would be run”.

I would imagine HexOS as a VM would work the same as TrueNAS does since they only add on not replace anything of TrieNAS Scale, so if the simplified management is good for you then why not?

The installer seems to expect an OS drive plus two drives for data which it will set up as a mirror (RAID1), so while TrueNAS/ZFS may work with a single data disk, HexOS might not let you complete the setup.

In the top menu under the “Activity” section

Just remember that if you want to move from a mirror of 2 drives to a raidz2 of four drives you would need to wipe and start over with the array, meaning having somewhere else to store the data temporarily.

Ah I guess it would default to only allowing a RAID1 or RAID5 during initial setup, that's what I would do in the situation of trying to make a simple NAS software that protects users from most ways of shooting themself in the foot 🙂

I didn't think Keith understood it, nor was your prior post offering any explanation under the hood. Over here it is stated that users will always be able to do things directly via TrueNAS, so if someone is knowledgable or has sufficient handholding they could do the RAID0/1 -> RAID10 migration by hand. As long as the pool mounts the rest of the automation shouldn't care. Based on the other answers that a 2-drive pool won't be expandable, I don't expect them to put effort in making this a builtin option (nor does TrueNAS [EDIT: TrueNAS' interface can handle RAID1 -> RAID10 but not a simple zvol to mirror zvol as far as I know])

This isn't really a HexOS thing, but an OpenZFS thing (which is the basis of TrueNAS as well) ZFS pools are made up of one or move volumes, called zvols, and each zvol is independently responsible for data redundancy. If there is one zvol then you can pretend the rest of this doesn't exist, but if there are two or more zvols the data will be striped across them (like RAID0 except chunks of data are assigned to zvols, instead of bytes) Making ZFS equivalents of common RAID types involves some mixing and matching. RAID0 - each disk is its own zvol, the pool contains one zvol per disk and allocates data across all of them RAID1 - a single zvol of the "mirror" type contains all disks RAID10 - each pair of disks is a separate mirror zvol, all the zvols are placed into the pool. RAID5/6 - all disks are placed in a single "raidz1", "raidz2", "raidz3" zvol, where the number indicates how many parity disks should be used RAID50/60 - create as many raidz zvols as you want (each with at least 3 disks) and add them all to the pool to be striped Remember I am purely talking about OpenZFS here, the concepts below might not be implemented in HexOS' management UI, but could be done manually using the local TrueNAS Scale UI/CLI (with the appropriate knowledge expectations and risks) With 2 disks you can either make a RAID0 (two single-disk zvols) or a RAID1 (one mirror zvol). When adding a single disk to a RAID0, you are simply expanding the storage and not introducing redundancy. When adding two disks to an existing 2-disk RAID0, you can convert this to a RAID10 by converting the two single-disk zvols to mirror zvols. When adding two disks to an existing 2-disk RAID1, you can add the new disks as a second mirror zvol, resulting in RAID10 OpenZFS has no mechanism to convert a single-disk or mirror zvol to a raidz zvol (can't convert RAID0/1 to 5). Other NAS systems that are capable of this are using mdadm or a bespoke RAID software. With relatively recent new code (released as Stable only a few months ago) ZFS is now able to expand raidz zvols one disk at a time, and additionally is able to move from raidz1 to raidz2 or raidz2 to raidz3 (add the new disk's space as parity instead of data)