Recover data after replacing USB drive

[MaskedGeek]

Hi,

 

I had a generic 1GB USB drive for my Unraid Server OS boot drive.  Everything was fine until I decided to stop my array to rename my device from Tower to a custom name in settings.  As soon as I did that my USB drive failed.  Despite all best efforts, that USB is dead so I've had to re-download Unraid OS onto a new USB drive.  Question is though, since starting that new USB have I lost my data on my drives, or can I recover them with the new USB drive?

 

My array configuration was as such:

Parity drive: Seagate Ironwolf 4TB NAS drive

Data drives: 2 x Seagate Barracuda 3TB drives

Cache: Samsung EVO 850 250GB SSD

 

Before the USB failure, one of the Barracuda's was sat at exactly 50% usage, 1.5TB of used space, 1.5TB of free space. The other Barracude was at around 1TB of used space so had about 2TB of free space.  (Oh and if anyone is asking why I have a 4TB parity, later on I intend to have 4TB data drives)

 

I know in general 1 parity drive helps recover data from 1 failed data drive, but since non of my array drives failed, will the data be still there?

 

TIA.

[JonathanM]

Your data will be fine. Any containers and VM's will have to be rebuilt, but as long as the drives are assigned in the correct slots, all your data will show back up just fine. Shares will no longer have any security customizations, so be sure to go into the shares page and set them to restrict access if desired.

 

Do you have ANY files backed up from your old USB?

[MaskedGeek]

HI Jonathan, with the old USB stick, I could read from it but not write to it.  Tried using Disk Management under Windows (as well as a Windows app called BootICEx64), and also tried Disk Utility under macOS to try to reformat the USB stick, but it was nothing but errors so safe to say that USB is dead.  However when I got the first error from Unraid OS saying it couldn't write to the USB I copied the files off of it onto my Windows PC.

 

I won't bore with all the details but I spent around 3 to 3 1/2 hours going through support docs to create a new USB and copying back on to it first all files, then only the "config" folder, but the server threw up all kinds of "unable to create session ID" errors.  In the end I just created a new USB and in essence, a new server linked to my account.  Fortunately I'm new to Unraid so still using the trail key for now so no loss of key there.

 

When assigning the drives again, I kept getting warnings saying data would be destroyed but just reassigning drives for testing, I realized the warning only applied to the parity drive.  I assigned the drives back to where they were, noticed a tick box next to the "Start" button saying "Parity already valid" and started the array.  To my relief, yes like you said, the data was there and the parity wasn't rebuilt.  Though to be extra safe I'm running a parity check.

 

Sweats over though.  I'm good.

[Squid]

17 minutes ago, MaskedGeek said:

"unable to create session ID"

Did you shut down the server before copying back and forth the /config folder and then replacing it?

[MaskedGeek]

20 minutes ago, Squid said:

Did you shut down the server before copying back and forth the /config folder and then replacing it?

Yep. As soon as Unraid gave me the first write error I didn't want the server to crash so I shut it down. All USB file operations were done on my Windows PC. The session ID error was a result of creating a new USB from creator tool then copying back all files from the backup. If I copied back just the /config folder I think I got a boot error. I run the server headless so I would only know if boot was successful if I saw the server and it's IP address listed in my router.