Restarting / Rebooting Hyper-V virtual machine while backing up - opinions/facts needed


- Hyper-V Host with different VMs
  - Different VM types (fileserver, sql-server, exchange server etc.)
- Backup-Exec Server backing up the Hyper-V Host guests through Hyper-V Agent
- GRT activated, RA inside the VMs

How is the backup affected, when restarting certain VMs during backup at night (for windows updates f.e.)?
Any impacts?

I think, it should not have any impact. But what about application-consistent backups, could these be a problem?
Thanks for sharing your experience/opinions.