Windows warning about corruption in VeeamFLR

[pshute]

I found this error in our Veeam server's System Event Log (EventID 55):
"A corruption was discovered in the file system structure on volume C:\VeeamFLR\NVSM1_209f77e3\Volume2. The exact nature of the corruption is unknown. The file system structures need to be scanned online. "

I ran chkdsk, and it fixed some stuff:
CHKDSK is verifying security descriptors (stage 3 of 5)...
Cleaning up 204 unused index entries from index $SII of file 0x9.
Cleaning up 204 unused index entries from index $SDH of file 0x9.
Cleaning up 204 unused security descriptors.

I haven't seen corruption reported to the folder level before. Should I be worried about this? What's in that folder? In c:\VeeamFLR I see that folder containing three empty folders called Volume1, 2 and 3. In the other folder are three similarly named junction points that don't let me open them.

The event log entries were from two months ago, and haven't been reported since. Does that mean whatever the problem was has fixed itself?

[jmmarton]

When you perform FLR for a Windows VM, the disks for the VM are mounted from the backup repository underneath C:\VeeamFLR. A folder is created using the name of VM_id so in your case you performed a restore of a VM called NVSM1. Underneath that everything is just mount points to the volumes that were backed up. There's no need to perform chkdsk since there's no actual data there. My guess is that there was an issue with the filesystem represented as "Volume2" in NVSM1 before it was backed up. And at this point if that folder structure is still there underneath VeeamFLR and you don't have active FLR activity for this VM in progress you can safely clean it up.

Joe

[pshute]

Thanks, yes, that makes sense. I checked that server, and there is indeed disk corruption logged in its System Event log, and a test run of chkdsk says it's still there.

I also tried restoring a single file from its most recent full backup, and a single email (it's an Exchange server). But no corruption of the mounted file system was logged in the backup server's event log. I'm curious to know why it logged it in the past, but not today. What would trigger it? Maybe it just needs to be mounted for a long time, and Windows will eventually check it? Maybe not a Veeam issue.

[albertwt]

Does this issue happen after applying the 9.5 Update 1 or Update 2 has fixed it ?