Added 2 NVME drives and can only choose RAID0 or Mirror ... No Single Mode

[bugsysiegals]

Per the title, I added 2x 2TB NVME drives to my server. I formatted both as ZFS, created a pool, added both devices (Cache and Cache 1), selected the Cache, and can only select ZFS RAID0 or Mirror.  Whether I start or stop the array I cannot get to any place for Balance or to select Single mode.  What am I doing wrong?  I'm on version 6.12.4.

[MAM59]

you need to create TWO pools and put only one drive into each of them

 

(create pool first THEN put a disk into it and THEN format)

Edited November 28, 2023 by MAM59

[itimpi]

4 hours ago, bugsysiegals said:

Per the title, I added 2x 2TB NVME drives to my server. I formatted both as ZFS, created a pool, added both devices (Cache and Cache 1), selected the Cache, and can only select ZFS RAID0 or Mirror.  Whether I start or stop the array I cannot get to any place for Balance or to select Single mode.  What am I doing wrong?  I'm on version 6.12.4.

The 'Single' option you mention only applies to BTRFS pools as far as I know.

[JorgeB]

Also note that with btrfs single mode has no advantages when using 2 same size devices, it still stripes the data and it's slower than raid0.

[bugsysiegals]

9 hours ago, MAM59 said:

you need to create TWO pools and put only one drive into each of them

 

(create pool first THEN put a disk into it and THEN format)

 

I've around 250GB being used for appdata, data (recently downloaded media before offloading to the array), domains, isos, system (libvirt), and docker.img.  I was hoping to use the remaining 1.75TB  on this drive and 2TB on the other drive for downloading media and hosting it here until it's 90% full at which point I begin offloading the oldest files to the array.

 

I'd wanted to keep these in the same pool in order to use a single path in all of my dockers for downloaded media.  I suspect 'll  lose this ability if I put these in 2 separate pools?

[MAM59]

38 minutes ago, bugsysiegals said:

I suspect 'll  lose this ability if I put these in 2 separate pools?

Yes, but it does not matter.

You can select seperate "pools" (disk) for any share, they do not need to belong together.

For instance:

you see? appdata is on pool "force510cruical" whereas domains (and later on system) is on pool "VM".

Each share has its own setting.

You can split as you wish (on top level).

 

[bugsysiegals]

1 hour ago, MAM59 said:

Yes, but it does not matter.

You can select seperate "pools" (disk) for any share, they do not need to belong together.

For instance:

you see? appdata is on pool "force510cruical" whereas domains (and later on system) is on pool "VM".

Each share has its own setting.

You can split as you wish (on top level).

 

 

Thanks for sharing how you can assign shares to different pools but this would mean I'd only be able to assign 1 pool/drive to "movies" and the data could not "spillover" onto the NVME which only has appdata, domains, isos, docker.img, and libvirt so this disk would always sit with 1.75TB of unused space.  Instead, I'd like the NVME pool to behave like the array, just without without parity, so  /mnt/cache/movies/ will find all movies regardless of whether it's on NVME1 or NVME2 just like the array does with /mnt/user/movies.  This allows me to use both NVME fully without 1 sitting there only consuming 250GB since appdata, domains, isos, Docker.img, and Libvirt will never grow much bigger for me.  I was thinking the single mode was doing what I'm saying but perhaps it's something not yet implemented into unRAID?

[JorgeB]

19 minutes ago, bugsysiegals said:

I was thinking the single mode was doing what I'm saying

As mentioned raid0 with same size devices is the same, or even better since it's faster, and there's no single mode with zfs, only btrfs.

[MAM59]

2 hours ago, bugsysiegals said:

Instead, I'd like the NVME pool to behave like the array

Ok, I've got it finally 🙂

But as far as I know, it is not possible yet with UNRAID.

Future Versions may get the option of "multiple arrays", but currently there are two problems in your way:

* there is only ONE "UNRAID Array"

* SSDs inside the array do not get proper trimming support (so they slow down extremely over time)

 

Both are worked on I think, stay tuned.

 

[bugsysiegals]

1 hour ago, JorgeB said:

As mentioned raid0 with same size devices is the same, or even better since it's faster, and there's no single mode with zfs, only btrfs.

 

I'd not chosen raid0 to potentially avoid wasting time rebuilding the "appdata" drive assuming it wasn't the one to fail but I think I should've chosen raid0 ... I was planning to run a script to backup critical files anyways so the downside of raid0 is having to copy critical files back from the array where I had a 50% of avoid with mirror but the benefit is using all the disk space of both drives and a potential speed increase?

 

 

[JorgeB]

2 minutes ago, bugsysiegals said:

I'd not chosen raid0 to potentially avoid wasting time rebuilding the "appdata" drive assuming it wasn't the one to fail but I think I should've chosen raid0 ...

That's not how it works, single mode, available for btrfs only, also stripes the data, so losing a device you will always lose the complete pool, the only advantage of single profile with btrfs is that it can fully use devices with different capacities, unlike raid0.

[bugsysiegals]

3 hours ago, JorgeB said:

That's not how it works, single mode, available for btrfs only, also stripes the data, so losing a device you will always lose the complete pool, the only advantage of single profile with btrfs is that it can fully use devices with different capacities, unlike raid0.

 

Thanks for the clarity, learned something new today!  I assume XFS behaves in the same way which is why unRAID allows you to add different size disks to the array?  Since my cache disks are the same size and I'd like the advanced features of ZFS I'll go with raid0, thanks again!

Edited November 28, 2023 by bugsysiegals

[Kilrah]

XFS only supports single drives, so you can't use it in multi drive pools.

Array is all single drive filesystems, with an extra separate layer on top that merges directories from multiple independent filesystems.

 

Basically in pools you use the filesystem's features, while in the array you use unraid's features that work regardless of the filesystems.

Edited November 28, 2023 by Kilrah