Workaround found here https://xcp-ng.org/forum/post/94626

Seems like turning "Use NDB to transfer disk if available" switch ON and save backup job,
then turn the switch OFF and save backup job again, will fix the issue.

Thanks to @RobWhalley and have a nice day everyone.

@RobWhalley Thank you... Works for me as well, good job!

Have a great day everyone.

My XO VM Backups were working just fine till last update that I did last night.

From today the XO VM Delta Backup says "Started" but never "Successful" (it is never completed).

• I'm on XO (built from source) and trying to do Delta Backup of my XO VM to NFS share.
• I don't see any recently unfinished Tasks.
• Other VM backups are "Successful".
• XO config and Pool Metadata are "Successful".
• NFS Remote on latest version of TrueNAS scale Test Passed OK.
• Local Storage (where XO VM resides), XCP-ng host and NFS share all have plenty of free storage space available.
• I did already restart of everything, TrueNAS, XCP-ng host and XO VM it self.

Nothing helped so far.

I'm on latest XO version from 30/06/2025 - commit no. 48bf9c9

Any idea where to start troubleshooting steps? Should I try to rollback previous snapshot that is still available?

Thank you in advance for your kind help, any information appreciated.

Have a great day, regards,

Vladislav