My organization runs a Hyper-V host with a couple of virtual machines, but we currently have no automated backup process. Some of the software inside the VMs does not handle being paused or restored while running, and I am not sure which backup products properly support VSS or application-consistent checkpoints. Because of that, we have been shutting the VMs down and making manual cold backups. I have looked at Windows Server Backup and Synology Active Backup for Business, but I have not been able to determine whether either can perform suitable backups without causing problems. What backup approach or software would you recommend?
4 Answers
For Hyper-V, check whether each VM can create a production checkpoint. In the VM's Integration Services settings, the Backup or volume-checkpoint option should be enabled. A production checkpoint uses VSS to create an application-consistent snapshot without the noticeable pause associated with a saved-state checkpoint. If the guest cannot quiesce successfully, Hyper-V may fall back to a saved-state or crash-consistent snapshot, which could explain why the software misbehaves.
Veeam Backup & Replication Community Edition is probably worth looking at if your organization qualifies. It can protect Hyper-V VMs through the host APIs, so you do not necessarily need VSS working inside every guest. It takes some time to configure correctly, but the documentation and tutorials are helpful.
Before choosing a product, identify what the software inside the VMs actually is. If it uses a database, ask the vendor whether it supports a pre-backup shutdown and post-backup startup task. A scheduled job can stop the database cleanly before the backup and bring it back afterward, producing a much safer application-consistent backup than simply pausing the VM.
That is an ideal solution when the vendor supports it. It avoids relying on the application being able to recover from a saved-state snapshot.
Avoid treating the backup software on the NAS as the whole strategy unless it has solid Hyper-V integration. A host-level product such as Veeam or another Hyper-V-aware platform is generally a better fit. Also make sure at least one backup copy is stored off-site; having only local backups will not protect you from a server, storage, or office disaster.
Some host-level backup tools let you choose the VSS behavior per protection job or VM. Disabling guest quiescing can avoid a problematic pause, but the resulting backup is crash-consistent, so the application and database vendor should confirm that this recovery method is acceptable.