Veeam and Windows 2008 System State Backup

[m.novelli]

On many Windows 2008 and Windows 2008 R2 VM I've scheduled a System State Backup with internal wbadmin Widows command
This command call Windows VSS writers and perform a local backup of System State. This backup is generally really slooooow, from 30 minutes to 1 hour.

My doubt is: I have to worry if Veeam Backup start during Windows System Backup? Veeam VSS can interfere with Windows System State Backup running?

Many thanks

Marco

[Gostev]

Hello Marco, based on my understanding on how everything works, Veeam VSS should not interfere with Windows System State Backup running, unless they both start at the same time (within 1 minute). But I will double check with devs tomorrow. Thanks!

[Vitaliy S.]

Hi Marco,

Let me put my two cents in. When you create a snapshot with Veeam VSS option checkbox enabled all Windows VSS writers are instructed to flush all I/O buffers prior to creating a snapshot. You will see the same behavior while using System State Backup (with wbadming command).

As the default window between the Freeze and Thaw events is typically 60 seconds in Windows, there is a little chance for Veeam backup job of getting into the same freeze window triggered by wbadmin Windows command. In this case we will trigger another time window for VM freezing. Basically you need to flush all I/O buffers to create a consistent snapshot. If the snapshot creation for your VM doesn't take much (not more than few seconds) and fits in the freeze window triggered by System State Backup (for example), then you won't see VSS failures in Veeam backup job either.

But to avoid any failures I would still recommend to use different backup windows for both backups.

Thanks!

[jgremillion]

Does the Veeam VSS agent backup the system state at the time of the Veeam backup?

[Gostev]

No, it only coordinates OS freeze before VMware snapshot is taken.

[jgremillion]

Can you get a successful VM server restore without a backup of the system state? Is this some thing that we should be scripting to do before the backup is taken?

[Gostev]

Sure, Veeam image level backup is all you need for successful VM restore.