As of generation Microsoft Server 2012 there is the option to back up your virtual machines using the GUI wizard. The strange thing though is that when I selected the VM (in this case PC02, see image below) the Hyper-V server insisted on (Backup Using Saved State). Now for what I was sure – Server 2003 and above (my case) that have the latest Integration Services installed things like snapshotting and backup ‘should’ work on a running machine. I mean, hello, MS is swanking around its Linux OS support based on these Integration Services, and further on Server 2003 supports VSS out of the box. So what was the problem?
After searching useless blogs and comments I came upon a document called ‘Protecting Hyper-V Virtual Machines’, featuring DPM 2012 SP1: http://technet.microsoft.com/en-us/library/hh757970.aspx
Guess what? There you find the list of all conditions that are preventing the backup in online state:
- The Backup (Volume Snapshot) Integration Service is disabled or not installed.
- A virtual machine has one or more dynamic disks.
- A virtual machine has one or more volumes that are based on non-NTFS file systems.
- In a cluster configuration, the virtual machine Cluster Resource Group is offline.
- A virtual machine is not in a running state.
- A Shadow Storage assignment of a volume inside the virtual machine is explicitly set to a different volume other than itself.
Pay attention especially to number 2. No dynamic discs are supported. Nuts. So if you want to back up a running machine it has to have a fixed disk. So long thin provisioning.
“Pay attention especially to number 2. No dynamic discs are supported. Nuts. So if you want to back up a running machine it has to have a fixed disk. So long thin provisioning.”
-> No, you must have a base disk Inside the VM, not a dynamic one
using a thin provisioning vhd is ok
Hi Fabien. Very interesting. Can you please elaborate on that? How is a fixed disk thin provisioned within the scope of Hyper-V, considering that not all types of companies can afford SAN solutions?
I just want to say that on the guest OS all volumes must are basic disks and there are no dynamic disks.
On the Host, you can use dynamic VHD.
Source : http://msdn.microsoft.com/en-us/library/dd405549(v=vs.85).aspx#details_on_the_hyper-v_vss_writer
Hi Fabien,
interesting point: you are interpreting the dynamic disk from the “internal” VM perspective. That’s legitimate.
I was using this term in its second meaning as a type of VHD – fixed, dynamic, differencing; hence my interpretation.
But if you are correct, as I am using a VM-perspective-basic-disk on a Hyper-V-perspective-dynamic-virtual-disk, why did I receive this warning then?
I don’t know I have the same issue with some VMs on some Hosts and I don’t understand why.
I think I’ll open a ticket with Microsoft.