error -3960 ( cannot quiesce virtual machine)

[scgsg]

Hi,

I'm completely new to this so please excuse me.

I've been trying to get vdr to backup a Windows Server 2008 r2 x64 VM but im getting the above error, can anyone help?

[FranckRookie]

Hi Scgsg,

Welcome to the forums.

Just an idea: check that your VDR VM is able to resolve vCenter and ESXs DNS names, either using DNS server or local hosts file.

Hope it helps.

Regards

Franck

[scgsg]

Thank you.

I think they are resolving fine but i will double check.

EDIT: OK checked and all names resolve.

[scgsg]

I forgot to add that the server is a DC.

[f10]

I have come accross this error when VDR is unable to quiesce the Guest O.S or if there are existing snapshots. Here's what I would do:

1. Go to Snapshot Manager, create a new snapshot and then Click on "Delete All" this will write the data on any existing snapshots to the base virtual disk.

2. Do a custom installation of VMware tools and exclude the VSS drivers. Use the VSS drivers provided by windows to quiesce the snapshot.

All the best

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

f10

VCP3,VCP4,HP UX CSA

[FranckRookie]

Backup a DC with snapshot: bad idea!

From Virtualizing a Windows Active Directoy:

• Avoid snapshots or REDOs for domain controller virtual machines.

• Do not suspend domain controller virtual machines for long periods.

• Perform consistent and regular system state backups.

• Never attempt to recover an Active Directory database from a backup copy of an old virtual disk.

Franck

[scgsg]

Thanks so much for all the help and advise, I was called away yesterday so had to stop looking into this.

@Franck: Thanks for the white paper its useful, I've only skimmed it so sorry if this has been covered by the white paper but whats the best practice to backup the VM. I have DPM backing up the system state but I'm not sure the best way to backup the VM.

[FranckRookie]

One solution is to have a backup application (or a backup agent) in your guest that is able to achieve Active Directory backups.

If you don't need backup but only redundancy, you can have another VM working as a DC. In case of a failure of one of them, switch the FSMO roles to the other one.

Here is a link to an article from Microsoft about things to consider when you host Active Directory domain controllers in virtual hosting environments

Regards

Franck