Hyper-V guest VM may become unavailable during backup
Enable online backups of Hyper-V guests
When a backup initiates, the Hyper-V guest becomes temporarily inaccessible.
There are several requirements to perform online backups of Hyper-V guests. If these requirements are not met, there can be brief unavailability of the guest while backups are running.
Make sure the following requirements are met on the guest VM:
- Integration services must be installed and running on the guest
- VSS snapshot storage on host must be on the same volume as your .vhd/vhdx files
- Guest disks must be basic, not dynamic
- Guest file system must be NTFS
Note that if these requirements are not met, backups should still run successfully. However, the guest will most likely become temporarily unavailable.