Multiple drives in a JBOD pool - sanity check

[MrDatum]

I want to backup a number of my home computers to my Unraid server. Some of the backup files are multi-terrabytes. I have been using a share with a couple of drives on the array, but I'm running into an issue where the backup fails as their isn't enough room, although I have TB's of space available. However, that space is spread over a couple of drives and I don't have the size needed on any one of those drives for the large multi-TB backup file.

 

1. Is it possible to create a JBOD pool where all of the drives are combined into one large drive such that a single large multi-TB file can span across more than one of the drives?
2. If so, can the drives be of different sizes?

 

Would this be the best way to accomplish what I am trying to do with my backups?

[trurl]

You can consolidate free space to one drive using some of the features of the unBALANCE plugin, or move things yourself using the Dynamix File Manager plugin.

 

It is possible to create multi-disk pools outside the parity array using btrfs:

https://docs.unraid.net/unraid-os/manual/storage-management/#why-use-a-pool

 

If you want to combine the capacity of multiple disks of different size, you would use the Single profile:

https://docs.unraid.net/unraid-os/manual/storage-management/#change-pool-raid-levels

 

Pools can also be ZFS but I have no experience with that.

[MrDatum]

3 hours ago, trurl said:

You can consolidate free space to one drive using some of the features of the unBALANCE plugin, or move things yourself using the Dynamix File Manager plugin.

 

It is possible to create multi-disk pools outside the parity array using btrfs:

https://docs.unraid.net/unraid-os/manual/storage-management/#why-use-a-pool

 

If you want to combine the capacity of multiple disks of different size, you would use the Single profile:

https://docs.unraid.net/unraid-os/manual/storage-management/#change-pool-raid-levels

 

Pools can also be ZFS but I have no experience with that.

Thanks, I'll give this a shot.

[MrDatum]

I'm about to setup my new pool but wanted to confirm that a single large multi-TB file can span across more than one of the drives in the pool so that I don't run into the issue of my backups failing because there isn't enough space.

For example, if I have a 3TB and another 3TB drive, and my backup file is 4TB, setting up a pool and selecting the Single profile will allow the 4TB file to span across both drives?

Edited December 21, 2023 by MrDatum

[JorgeB]

22 minutes ago, MrDatum said:

I'm about to setup my new pool but wanted to confirm that a single large multi-TB file can span across more than one of the drives in the pool so that I don't run into the issue of my backups failing because there isn't enough space.

It's not a problem with pools, only the array, where each disk is an independent filesystem.

[MrDatum]

Thanks for the help, it is working and I have that warm fuzzy feeling from being fully backed-up

In the future if I need more space in the pool can I just expand it by shutting down the array, adding another dive and then assigning that drive to the existing pool?

[JorgeB]

45 minutes ago, MrDatum said:

In the future if I need more space in the pool can I just expand it by shutting down the array, adding another dive and then assigning that drive to the existing pool?

Depends on the filesystem and pool topology you are using.

[MrDatum]

I'm using BTRFS in Single profile.

[MrDatum]

On 12/27/2023 at 9:54 AM, JorgeB said:

Depends on the filesystem and pool topology you are using.

Would using BTRFS in single profile allow me to expand the cache easily by adding another drive?

[JorgeB]

Yep, same for ZFS stripe (raid0 in the GUI)

[MrDatum]

Awesome, thanks!