I just received a new X15 server which comes with a 1TB m.2 nvme drive. 32GB has been used for an internal boot partition and the rest is just unused space that I would like to use for cache. Google says it can be done but not how. Is there some way to just assign it or do I need to do a new config?

Or maybe I could just create a cache.cfg file?

Edited May 19May 19 by wgstarks

You can just use it as a normal pool.

9 hours ago, wgstarks said:

I just received a new X15 server which comes with a 1TB m.2 nvme drive. 32GB has been used for an internal boot partition and the rest is just unused space that I would like to use for cache. Google says it can be done but not how. Is there some way to just assign it or do I need to do a new config?

Or maybe I could just create a cache.cfg file?

Boot is the name of the pool, When you start the array you will have the option to format(File system type). By default it will format to xfs but if you want some thing different like btrfs or zfs click on the name and set there. If you want to change the name from boot you can rename it by clicking the name in the disk info page where you set the format.

If you plan to install a 2nd device to make it mirror, then I would select btrfs or zfs as the format.

3 hours ago, SimonF said:

Boot is the name of the pool, When you start the array you will have the option to format(File system type). By default it will format to xfs but if you want some thing different like btrfs or zfs click on the name and set there. If you want to change the name from boot you can rename it by clicking the name in the disk info page where you set the format.

If you plan to install a 2nd device to make it mirror, then I would select btrfs or zfs as the format.

So I can just change the name to Cache? Is there another step to actually assign it as Cache? My old machine has been setup for years and I really don’t remember the process.

1 hour ago, wgstarks said:

Is there another step to actually assign it as Cache?

You do not have to rename the pool to ‘cache’ - it can be anything you like. It is just that for historical reasons ‘cache’ is the default name for the first pool. Whether a share should be cached is set at the individual share level and different shares could use different pools for caching purposes. To do so you set the pool to act as the cache (it can have any name) as primary storage, the array as secondary storage, and the mover direction as pool->array.

11 minutes ago, itimpi said:

You do not have to rename the pool to ‘cache’ - it can be anything you like. It is just that for historical reasons ‘cache’ is the default name for the first pool. Whether a share should be cached is set at the individual share level and different shares could use different pools for caching purposes. To do so you set the pool to act as the cache (it can have any name) as primary storage, the array as secondary storage, and the mover direction as pool->array.

But if I use the same name that was used when the shares were setup I won’t have to go back to each share and modify them, correct?

3 minutes ago, wgstarks said:

But if I use the same name that was used when the shares were setup I won’t have to go back to each share and modify them, correct?

Yes - but you should still check the settings for each share are what you think they should be.

2 minutes ago, itimpi said:

Yes - but you should still check the settings for each share are what you think they should be.

Thanks

On 5/20/2026 at 3:18 AM, SimonF said:

If you plan to install a 2nd device to make it mirror, then I would select btrfs or zfs as the format.

I’ll probably get another 1TB drive and add together with this partition in a mirrored drive. Does it matter whether I use btrfs or zfs? ZFS seems to be more popular in the Unraid forum.