Daily backup jobs just started failing - "The operation is not valid for Managed disk VMs." RRS feed

  • Question

  • In the last couple of days, I have started getting backup failures from a daily backup job that has been running for weeks.  In the Recovery Services vault, this machine has 27 crash consistent snapshots that have been taken with no errors using the same policy that is now giving failures.  The policy is once per day, instant recovery snapshot for 5 days, retention of backup for 30 days.  The oldest backup is now 30 days old.

    The error recorded states as follows and happens instantly at the scheduled backup time:

    Error code: UserErrorInvalidManagedDiskOperation

    Error message: The operation is not valid for Managed disk VMs.

    I am assuming that the backup job is having an issue deleting the oldest recovery point to make room for the most recent.  I have looked at the locks listed for the vault, but none are reported.

    Does anyone have thoughts on how to troubleshoot this issue?  Since I know the current state is good, I may just delete the entire set of backups and start fresh, but I'm concerned the issue will appear again in 30days.

    Thanks in advance for the suggestions,


    Joe McEwan

    Sunday, June 9, 2019 8:51 PM

All replies

  • Can you please check if the Write Accelerator is enabled on VM disks. If yes, kindly note that snapshot on the Write Accelerator enabled disk is not supported yet. This restriction blocks Azure Backup Service ability to perform an application consistent snapshot of Write Accelerator  enabled disks of the virtual machine. Therefore, the backup jobs keep failing. Kindly refer below official document for details.

    For more information, kindly refer this article.
    Thursday, June 13, 2019 4:33 AM