Unraid 6.12.6

Supermicro, dual parity, multiple data drives

Log files cannot be added as I cannot boot server

Historical: I had a dead hard drive that I was going to replace. I safely shut down from within Unraid, swapped the drive, and powered up.

Upon powering up, the server wouldn't boot due to USB errors and wouldn't get to the Login prompt. I shut down the server, put the USB boot drive in another Windows computer, saw Windows report there were errors on the USB, and I copied all contents from the USB to my Windows computer.

I repaired the USB and copied the USB to a DIFFERENT folder in Windows to maintain them separately. Apparently not all errors on the USB could be repaired. I tried booting Unraid anyway with it and it now gets to a login prompt but I still can't connect via the webGUI.

Additional: I use the flash backup tool to copy the flash drive to a PC so it is not in .ZIP format as I've read about recreating the USB with the USB Creation Tool - so there's no .ZIP I can point to. From the Unraid USB Creator, I can choose operating system "Unraid 6.12.15" (not the version I'm on - I know.. I'm behind updates) so I'm not sure if I should select that and then move the backed up "Config" folder over to the new USB.

I also went to Unraid Connect, and I swore I set this all up in the past, but there's no backups listed on there (page just keeps saying "Loading").

Question: How exactly do I recover my USB boot device? Do I just copy the contents of flashbackup to a new USB3.0 device and plug that in?

Thank you!

Edited May 10May 10 by ginch
Found Unraid version on the boot USB, more details about USB Creation Tool.

This is purely a boot drive issue and fully recoverable.

Use the Unraid USB Creator to create a fresh bootable drive on a new USB, selecting the current stable version (6.12.15 is fine -- you can update from within Unraid afterward).

Then copy your config folder from your flashbackup to the new USB, replacing what the Creator put there. That's it.

A few notes:

-- Don't copy everything from the flashbackup, just the config folder

-- The new drive will have a different GUID so you'll need to transfer your license. You get one self-service transfer per year via the Unraid Connect portal.

-- Once back up, avoid USB 3.x ports for boot.

-- While you're sourcing a replacement, check the Unraid Boot Devices Guide guide in the Boot Devices section of this forum.

If in a hurry, get Innodisk DEUA1-64GI61BW1SC -- industrial grade, around $4, plug into a USB 2.0 port.

Worth getting a couple while they're available at that price. eBay item number: 326046070546

Edited May 11May 11 by Lolight

Thank you Lolight, this was very helpful. Unfortunately the content on my USB drive was corrupt even after fixing the errors as I noticed the server was booting but wasn't resolving an IP address. After dumping the diagnostics and seeing that no IP was being issued, I checked the network.cfg file and found ascii characters that didn't belong in the file. I managed to recreate the network.cfg based on another post in the forum and then the server came online. The data drive has been rebuilt.

However I'm now seeing a new issue where (and probably because my config folder was out of date). I can create a new thread if you wish, please advise, but the long and short of it is that I had my cache drives in a RAID1 for redundancy. When I booted up after this fix, it showed only a "Cache 2" under "Pool Devices".

Under "Unassigned Devices" I see Dev 1 and confirmed it is the other cache drive. It had a button beside the drive identification that said [MOUNT] so I pressed that. It now shows the word "POOL" beside Dev 1 (under Unassigned Devices) but it doesn't show the drive as device "Cache" under "Pool Devices". I didn't want to start the array yet in case this would have negative impacts.

Much gratitude for your help.

Glad you're mostly back up. Don't start the array yet.

1. Click the POOL button next to Dev 1 in Unassigned Devices

2. Click Apply

3. The pool should return to mirrored state and resilver automatically

4. Once complete run a scrub on the cache pool to confirm integrity

Double check you're assigning the correct drive before clicking Apply.

Don't start the array until the pool looks correct.

Edited May 14May 14 by Lolight

The array had been started in maintenance mode in order to rebuild the original failed drive in the data array. I have stopped the array and unfortunately clicking the POOL button doesn't appear to do anything. It appears to be greyed out.

Array is currently in stopped state.

The greyed out POOL button with the array stopped is likely why it's not responding.

Try starting the array first -- in maintenance mode is fine -- and then attempt the POOL button again on Dev 1 in Unassigned Devices.

The array being started doesn't mean data is at risk here.

The cache pool issue is separate from the array drives.

If the POOL button is still greyed out after starting the array, post a screenshot of what you're seeing and it would be worth opening a dedicated thread for this specific issue to get more focused help.

Odd behaviour with this cache drive but I think I figured it out. I've marked the original solution you proposed as fixed.

I was unable to select anything as the first cache drive from the drive selection dropdown box, and it remained in the unassigned devices with the [POOL] button greyed out. I started the array in maintenance mode, then stopped it. The Cache#1 dropdown box then became populated with the drive that was listed in the Unassigned Devices section. I chose the drive (WDC...) as Cache#1 and got the warning that the contents would be overwritten, and I proceeded. I started the array again, not in maintenance mode, and it's appearing as a cache pool now (Image attached). I don't think I'll need to post a follow-up help for the cache drive issue, but is there any way I can verify that Cache#1 actually equals Cache#2? I suppose because there's only one button to browse /mnt/cache that should be enough to verify?

Either way, I've got lots of alerts to fix things, my Nerdpack and NUT addons appear to have broken throughout this.

Aside from having a pro license to support the Unraid community, how can I show my appreciation for your help?

Great result -- the pool looks exactly as it should.

To verify Cache and Cache 2 are consistent, run a BTRFS scrub on the cache pool.

It reads every block on both mirror members and compares checksums -- zero errors after completion confirms the mirror is healthy and both drives contain identical data.

On showing appreciation -- the best thing you can do is pay it forward.

When you see someone else on the forum in a similar situation, share what you learned.

That's how this community works at its best.