nmills3

is there a solution so switch to a 3 drive pool with 2TB of storage without needing to switch to zfs or is that my only option?

well it's not technically a new device, it's the old device being re added after an extended period of time, will the system just play nice with that or will it try and do something strange as it will recognise it as a previously existing disk in the pool? Also how hard should it be to convert the pool to a raid 5 after adding the drive back?

tower-diagnostics-20240403-1722.zip

So a while back i had to remove 1 disk of my 3 drive cache pool because of an issue that was causing write errors for the drive. Since then i've worked out that the drive is fine and that it was an issue with the sas to 4 x sata cable that i was using, i've replaced the cable now. How do i go about re adding the previously removed cache drive back to the cache pool? Before removing the drive the pool was made up of 3 x 1TB ssds and i think i had it as a mirror (yes that was dumb) and it had a total capacity of 1.5TB. After removing the drive the pool got converted into what i think is just a 2 disk mirror with 1TB of total storage. My goal is to re add the failed drive to go back up to 3 disks total and then i want to convert it into whatever raid will give me 2TB of storage with 1 disk being used for redundancy. Ideally it would be nice if there is a way to do this while leaving the data in place and not having to move everything to the array and then back onto the cache pool as the cache pool has a lot of tiny files and will probably take a long time to move over and back again

but when i removed the ssd and started the array a few days ago. it asked me if i wanted to remove the device and i said yes, shouldn't that mean it was removed from the pool?

Should i make this into a new post? i think this might be a bit outside of the scope of the original issue at this point

So i think i found a bug in unraid. It seems like that ssd that i removed a few days ago was causing the cache to not mount properly. With that drive installed but not assigned to the cache pool (it was a 3 drive pool with the 2nd slot unassigned) the pool would fail to mount, there was also an issue with the superblock size but that was fixed with the command "btrfs rescue fix-device-size" after running a check on the pool. Then when running a "btrfs filesystem show" command, i noticed it was listing the installed but not assigned drive as a part of the pool but with a different storage size (about 80gb less than the drives that were actually assigned to the pool). So i shut down and ripped out that drive again and now the server starts fine and the pool seems to be functioning properly. So i think that maybe when unraid removed the disk from the pool when i removed it the first time, it didn't actually remove it properly and it was still trying to use it as a part of the pool

@JorgeB so my situation has got even more strange. So i just replaced the cable and transfered the server to a new case without a cheap hot swap backplane and now the normal drives all seem to be working fine, but now my cache pool is completely dead. So i moved everything, checked all the disks showed up, re-assigned a disk to the main array that had a faulty cable and the started the array and now the cache that was working this morning as a 2 drive raid 1 is just showing 2 disks with the error "Unmountable: Unsupported or no file system". I have no idea what could have happened to them. I did a clean shutdown before hand and all seemed to be working fine since my last update, nothing seemed to be corrupted and everything was working, and now this has happened. tower-diagnostics-20231111-1817.zip

ok, i've disconnected both of the bad drives and it seems to be working now. The cache pool had enough space to just convert into a 2 drive raid 1 and the main array has been running with a missing disk for about 2 months already. So everything seems to be working now. I'm going to try and reinstall the ssd once the replacement cable shows up, but until then, at least the server can limp along. I'll attach new diagnostics anyway just incase there's anything useful tower-diagnostics-20231109-1056.zip

@JorgeB any other advice you have for what I can do would be appreciated

also ignore the drive errors from sde. that's an unassigned drive in a slot that i know is bad

so i just reseated the cables and restarted the server and now most of my docker containers using appdata won't start and a few of them have errors saying about a read only file system. The syslog also has some errors about a checksum and it giving a lot of I/O errors from the same drive as before. I'll attach a new diagnostic to this post. So on a scale of 1-10, how screwed am i in terms of the data on the cache pool? tower-diagnostics-20231108-2045.zip

tower-diagnostics-20231108-1938.zip i'll attach a diagnostics just in case it's useful

ok, the array finally stopped. Hopefully my cache data still exists

so i just tried stopping the array so that it wouldn't keep getting errors while i wait for a replacement cable. The server just sat with the loading thing for a while and wouldn't load any other pages. Now the web ui is responsive again but the array still isn't stopped and the log is filled with this message Nov 8 19:32:50 Tower kernel: BTRFS error (device sdf1): error writing primary super block to device 2 sdf is the first drive in the cache pool. but sdg which is the second in that pool is the one that was giving the crc errors