Flash Drive Failed

[potts.mike]

Over the weekend my flash drive failed. Everything has been running fine for years so I am a little rusty on the process. 

 

I plugged the old flash drive into my mac and can see most the files. I ran first aid on the drive and it passed but still wont boot. I got a new flash drive and installed the latest release on it. The machine is now booting fine but I am nervous to start the array as it says that the parity drive will be erased. I believe that I have backups stored on the array but don't want to accidentally erase them by starting it.

 

I also have a backup on Unraid connect that I can restore, Do I just copy those files to the usb or do I need to use the USB creator software to write the zip file to the new usb drive?

 

I am really just looking for any guidance or to be pointed to a good to tutorial on the best way to get back up and running without any data loss.

 

-Thanks

[Anon]

Hi,

 

as you still have the backup you can install it to the new usb-stick.

The general guide is listed here: https://docs.unraid.net/unraid-os/manual/changing-the-flash-device/

 

The specific part of the guide that explains how you can put the backup onto the new usb-stick:

 

[Frank1940]

You never really stated how you shutdown your Unraid server or how you found that the flash drive had failed.  One of things that happen when Unraid shuts down gracefully (or 'cleanly'), it sets a flag in a file on the flash drive to indicate that the array was shutdown properly.  (i.e., all of the cache buffers were flushed to the platters on the hard disks.)   When your drive failed (or was corrupted), this flag may not have been set (or you didn't restore the file that contains the flag.)  

 

What happens when Unraid boots up is that it checks for this flag.  If it does not find it, it assumes that parity is not correct and offers to rebuild parity.  The GUI informs you that starting the array will start a parity rebuild.  (Long experience has shown that this is usually the best option for most unclean shutdowns if all of the data drives can be mounted.)   This rebuilding parity check may or may not find any parity errors.  (There were discussions in the distant past as to whether it might be better to run a non-correcting parity rather than a parity rebuilt.  The problem was that if the non-correcting check found an error, it was almost impossible to find a cause-- and a solution --to fix the problem.  So a slow consensus was reached that rebuilding parity was the way to go.  That way, if there was a subsequent disk physical failure, that disk could be rebuild without a loss of the data on that disk--- Even if there was a data problem on another disk, that first disk with the failure could still be successfully rebuild.   If there was a case where parity could not be rebuilt, the disk with the problem would be revealed and that issue could then be addressed!) 

 

I would assume that all of your data on the data drives are OK unless there was a disk write operation going on when you actually shut the server down.  Most of the time, data losses occur when the server is forced down by a power failure.  I can not recall a data loss from a simple flash drive failure-- unless there was subsequent cockpit error.  One thing you should worry about is assigning a data disk as a parity disk.  (Rebuilding parity onto a data disk will result in data loss.)  But I would assume that you have already figured out (or knew) which drives were your data drives!  If you  don't, state so as there are ways to figure things out. 

 

 

[trurl]

As far as I know, unclean shutdown parity check is not correcting. Did this change?