Backup always use Microsoft VSS-FULL Option and breaks other Backups
Hello!!
At first, hope i'm right here!
We use Proxmox with qemu-ga. Backups are done with vzdump (integrated in Proxmox) and Bareos for second Backup-Strategy. Proxmox creates dly Imagebackups. Bareos creates Databackup for longterm archive.
Bareos creates a Fullbackup once a day and all few hours a incremental Backup. Bareos-Fullbackup use Microsoft-VSS-Option "VSS-Full" for SQL Log-Truncating. Bareos schould be the only one who use VSS-Full. So it's guaranteed that Bareos is able to restore all data all time
Proxmox vzdump Backups use fss-freeze with Qemu-GA Agent Qemu-GA always use VSS-Full. This breaks the Bareos Backup, because after vzdump Backup SQL also truncates the SQL-Logfiles
Mybe its possible to make a switch for VSS-Full or VSS-Copy Backups. So we cat set a Regkey or something else to tell Qemu-GA to user VSS-Copy Hope also Proxmox will integrate this feature in vzdump to select the VSS Option in Backupjob.
In File qemu/qga/vss-win32/requester.cpp Line 297 VSS-Full is hardcoded.
hr = vss_ctx.pVssbc->SetBackupState(true, true, **VSS_BT_FULL**, false);
Goal
Something like that
If Regkey
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\QEMU Guest Agent VSS Provider\VssOption
is set to VSS-Copy
qemu-ga use VSS-Copy instead of VSS-Full
Technical details
In File qemu/qga/vss-win32/requester.cpp Line 297, VSS-Full is hardcoded.
hr = vss_ctx.pVssbc->SetBackupState(true, true, VSS_BT_FULL, false);
A Switch that the qemu-ga schould use VSS-Copy would help.
Additional information
MS VSS-Options https://docs.microsoft.com/en-us/windows/win32/api/vss/ne-vss-vss_backup_type