Unmountable cache disk pool (After trying to replace a dead SSD)

[JorgeB]

11 minutes ago, REllU said:

would you have any ideas as of what actually happened here?

They were both wiped, this is why you needed to use the btrfs-select-super command, this was likely done by Unraid because of some misstep during the replacement, but if that was the only issue and it was a raid1 pool I would expect the good member to mount by itself, so there were/are other issues.

[REllU]

Hey again, took me a while. Moved to a new place after our chat, so things have been a bit hectic.

 

Anyhow!

I went through the steps in the thread you showed, and here's the results:

 

I have both of my servers in the same network right now, and I created a new share in to the main server (called "DataStriver") and mounted a remote share on the backup server to it.

I mounted the remote share, and then tried to do the backup from SSD to the remote share.

 

I'll throw the diagnostics for you.

datastriver-diagnostics-20210901-1528.zip

[JorgeB]

Looks like the fs is very damaged, you can try IRC as mentioned in the FAQ, it's frequented by very experienced btrfs users and some maintainers, they might be able to help more, but it doesn't look very good to me.

[REllU]

Right, in that case, I might just swap the SSD's entirely, and start the cache from scratch (as again, nothing important was lost with this. I really just wanted to learn how to handle issues like this, should they occur to the main server. But seems that this is a rather rare situation)

 

Just tossing a (probably stupid) idea.

Since the SSD is constantly complaining about the missing device 2, would it affect anything if we tried to add in the failing SSD in there, so that the configuration was as it was originally, and then try to do recovery things? (though, that's what we did in the first place, I guess..)

Since both of the SSD's were already used, and pretty low-end consumer grade ones, my guess is that both of them were failing, but on a different level. 🤷‍♂️

[JorgeB]

6 minutes ago, REllU said:

Since the SSD is constantly complaining about the missing device 2, would it affect anything if we tried to add in the failing SSD in there, so that the configuration was as it was originally, and then try to do recovery things?

You can try, but the other device is out of sync.

 

 

[Crackwood]

On 8/23/2021 at 12:08 PM, JorgeB said:

mkdir /x
mount -o degraded,ro /dev/sdd1 /x

 

I owe you, my good sir, a beer!