Azure Backup: Backup runs only in copy mode

When using MaxBack to back up a virtual machine on Azure, you may notice that the backup history is not updated and/or log truncation is not working.

The MaxBack Session Log Viewer shows that the backups are being run in "Backup (Copy)" mode.

Solution

This is caused by an Azure Backup setting which - in recent versions - uses copy mode by default. See the Microsoft documentation for more information. 

If Azure Backup is your primary backup method (i.e. if you are not running Azure Backup as a secondary backup for an offsite copy), configure the following registry setting in the VM:

REG ADD "HKLM\SOFTWARE\Microsoft\BcdrAgent" /v UseVssFullBackup /t REG_SZ /d True /f