MSSQL Backup Error when proxmox create snapshot


Nov 22, 2018
Hi, when i create backup image in proxmox, using mode "Snapshot", MSSQL writes to windows log:

SQLVDI: Loc=SignalAbort. Desc=Client initiates abort. ErrorCode=(0). Process=18352. Thread=13404. Client. Instance=. VD=Global\{876B455A-D199-49C1-9020-FC332E89E10D}33_SQLVDIMemoryName_0.
BackupVirtualDeviceFile::SendFileInfoBegin: failure on backup device '876B455A-D199-49C1-9020-FC332E89E10D}26'. Operating system error 995(The I/O operation has been aborted because of either a thread exit or an application request.).
and vss

VSS Volume Shadow Copy Service error: Error calling a routine on a Shadow Copy Provider {00000000-0000-0000-0000-000000000000}. Routine details CommitSnapshots [hr = 0x80004005, Unspecified error ]. Operation: Executing Asynchronous Operation Context: Current State: DoSnapshotSet

As a result, Proxmox backup is ok. And when i disable Qemu guest vss provider - i've not see this errors.

Why this happens?

I have another VM with MSSQL on the same node, and using snapshot mode it completes without errors in MSSQL journal.

pveversion --verbose
proxmox-ve: 5.3-1 (running kernel: 4.15.18-11-pve)
pve-manager: 5.3-9 (running version: 5.3-9/ba817b29)
pve-kernel-4.15: 5.3-2
pve-kernel-4.13: 5.2-2
pve-kernel-4.15.18-11-pve: 4.15.18-33
pve-kernel-4.15.17-1-pve: 4.15.17-9
pve-kernel-4.13.16-4-pve: 4.13.16-51
pve-kernel-4.13.16-2-pve: 4.13.16-48
pve-kernel-4.13.16-1-pve: 4.13.16-46
pve-kernel-4.13.13-6-pve: 4.13.13-42
corosync: 2.4.4-pve1
criu: 2.11.1-1~bpo90
glusterfs-client: 3.8.8-1
ksm-control-daemon: not correctly installed
libjs-extjs: 6.0.1-2
libpve-access-control: 5.1-3
libpve-apiclient-perl: 2.0-5
libpve-common-perl: 5.0-46
libpve-guest-common-perl: 2.0-20
libpve-http-server-perl: 2.0-11
libpve-storage-perl: 5.0-37
libqb0: 1.0.3-1~bpo9
lvm2: 2.02.168-pve6
lxc-pve: 3.1.0-2
lxcfs: 3.0.2-2
novnc-pve: 1.0.0-2
proxmox-widget-toolkit: 1.0-22
pve-cluster: 5.0-33
pve-container: 2.0-34
pve-docs: 5.3-2
pve-edk2-firmware: 1.20181023-1
pve-firewall: 3.0-17
pve-firmware: 2.0-6
pve-ha-manager: 2.0-6
pve-i18n: 1.0-9
pve-libspice-server1: 0.14.1-2
pve-qemu-kvm: 2.12.1-1
pve-xtermjs: 3.10.1-1
qemu-server: 5.0-46
smartmontools: 6.5+svn4324-1
spiceterm: 3.0-5
vncterm: 1.5-3

qemu-guest version - 7.6.2
As a result, Proxmox backup is ok. And when i disable Qemu guest vss provider - i've not see this errors.
When the guest agent is disabled the OS inside doesn't know about the snapshot of its VM images. This can lead to an inconsistent state of the DB, as it doesn't know that it has to sync its data to storage.

Why this happens?
Check if the snapshot provider is working on Windows and if there is an qemu-guest-agent update to install.


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