Refs recovery

[lohelle]

Hi.
This is not a Veeam issue, but related to backups with REFS block cloning.

Every year around this time of year I move a big chunk of our GFS archives for the last year to a different server (turned off except during file copy).
I've just moved around 100TB of data to the "offline-copy-server" to a REFS volume backed by a RAID50 volume.
file copy was successful, and I only had to turn on the server again because I wanted to add a few extra files to it.
I start a new fresh GFS-job for every normal backup job after the files are moved out of the "main" GFS storage server.

Now the problem.. The volume is shown as RAW. This is not related to the jan 2022 update (server was unpatched, but now updated to the latest December update for Windows Server 2022.

I can see some event log entries for "The file system detected a checksum error and was not able to correct it. The name of the file or folder is "Container Table"." etc.
It looks like refsutil salvage can copy the files, but I'm expecting this copy to not keep the block cloning, and the destination would need to be like 500-1000TB...

Anyone ever had any luck recovering from this? Raid controller has a BBU. But I had to force reboot the server because it hang during reboot. So I expect the corruption to happen during that.
Any advice?
And I guess it's not possible to "fix" the block cloning by first copying it, then moving it again using Veeam?

edit: I already have a single new GFS copy, but losing 1 year of history is bad. Even if I guess I can recover/copy only the needed files with refsutil salvage, import and then recover, if needed...

[lohelle]

I see that I might be able to move files from a temp recovery folder/drive to a new REFS volume and add fast-clone/block cloning back.. That helps a bit I guess. But I would need to recover and move files over like 10 sessions to not run out of space...