Hello there,

I'm running into a sort of a big problem. I'm running my rig on unraid version 7.0.1 in a cache pool only with 4 m.2 ssds in a zfs pool.

Now I wanted to add a gpu to the rig, but I'm using a mini-ITX mainboard and therefore have only 2 m.2 slots on the board. The other two ssds are sitting on a pcie adapter card.

To install the gpu I have to get rid of the m.2 adapter card. But I already tested, I will not be able to start the array with even a single drive missing.

 

I've searched many forum threads and videos, but I found no solution for my case with a cache pool only variant. Does anyone have an Idea on how I should go on from here and if I can decrease my zfs pool without having to reconfigure my shares and reinstall my dockers?

 

I'm very happy for any tips, trick,s and ideas.

Please post the diagnostics to see current pool config.
 

Here is the diagnostics.

pheonix-diagnostics-20250415-1831.zip

Note that you are using a striped pool, so there's no redundancy, but since it is a stripe, you can remove a device and keep the data, as long as it fits in the remaining devices, and you will need to use the CLI, since the GUI does not support that, if you want to proceed I can post the instructions, just let me know which device you want to remove.

Thanks for the quick response. Yes, I used striped pool since I planned with much more space needed than it actually turned out. The drives I want to remove are nvme0n1p1 (cache 1) and nvme1n1p1 (cache 3). The two on the adapter card that I use. But that's more a QOL thing, since I have no problem switching the SSDs to different slots if it's better to remove caches 3 and 4 and keep 1 and 2 for example.

The cache pool in its current configuration contains 4x the same 500Gb Crucial SSDs and is currently utilized with around 250GB of data striped pretty evenly on all 4 drives with between 58GB to 66 GB per drive.

 

If it's possible to remove the drives without losing any data, I'd welcome your instructions very much. Thanks a lot for that offer.

Oh, something that might be worth mentioning, I haven't upgraded the pool to a zpool. Do you have any advice on if I should do it before or not?

Edited April 16, 20251 yr by V4rynth
wrong word

5 hours ago, V4rynth said:

I haven't upgraded the pool to a zpool.

That doesn't matter for this, to remove a device, with the array running type:

 

zpool remove cache nvme0n1p1

 

When that's done, you can remove the other device, after both are removed , you need to reimport the pool, to do that, stop the array:

 

on main click on the first device for that pool and then "remove pool"
back on main, create a new pool with the same name and 2 slots
assign the remaining pool devices, leave the filesystem set to auto
start the array to import the pool

Alright, I've followed your steps and it seems like it worked. The pool now contains only 2 drives, the dockers are still working and it seems no data was lost. Perfect.

Thank you very much for your help.