Hello everyone,

I upgraded my license to unleashed during the sale, and I've been throwing every spare drive I can find into my server.

Previously, my cache pool included two SSDs, one 120GB and one 240GB. Since I didn't need the cache capacity, I had it setup for raid1. Everything was working fine. Then I decided to add a 500GB SSD to my cache. I plugged it in, and added it to my cache. The 500GB was not available, which is kind of what I expected if I was still in raid1 configuration. I tried to change the allocation profile to raid0 or single, and no matter what I do, cannot get it back to normal.

Even though the allocation profile is single, the cache data partition shows as degraded:

When I try to remove a drive (to a temporary second cache) to make unraid "forget" the previous configuration, I get the following error:

I find it especially strange the btrfs filesystem usage shows Id 2 as missing, when the 240GB SSD is still there:

I don't know how to remove the degraded cache error.

My goal is, without losing my current data in cache, to get to a single allocation profile where I can use all three (120+240+500) drives.

Any help you can provide would be greatly appreciated. Diagnostics attached. (I'm aware of the reallocated sector issues in the parity drive, the replacement drive should be here in a day or two).

Thanks,

Adam

diagnostics.zip

I'll let someone with more btrfs raid expertise help with your problem, but I thought I would comment on this:

1 hour ago, lessthanadam said:

I've been throwing every spare drive I can find into my server.

Only use reliable drives in your server, not just whatever you happen to have. In order to reliably rebuild a drive, Unraid must be able to reliably read all other drives in the array. So, a drive that isn't reliable could potentially compromise your ability to recover a different drive.

Also, I always say, each additional drive is an additional point of failure.

Use as many drives as required for your current needed capacity, plus some spare space. Don't fill up you server with drives just because you can.

The pool is currently only using one device; the other is missing.

First reimport the pool using only the good device (sdc)

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 1 slots

assign the good pool device, leave the filesystem set to auto

start the array to import the pool

The pool should be imported degraded, since it's using single profile, you will need to use th CLI to correct it, with the array running type:

btrfs dev remove missing /mnt/cache

Now reimport the pool once more with the single device, it should now be imported without being degraded.

If yes, you can now add one device and then the other one.