Subject Firebird Backups on Google Compute Engine

We are considering moving our systems to GCE and trying to figure the best approach to backup our many firebird databases.

Firebird is not VSS aware so we can't use shadow copying. On our current host, we create backups of every single database with gbak daily - which consumes a lot of time and disk. We would like to improve that.

Would the following procedure be enough to guarantee a safe differential backup? We are on windows :

  1. connect to all databases and set them to backup mode (or offline mode)
  2. stop the firebird service
  3. unmount the drive containing the dbs
  4. create a snapshot with gcloud
  5. remount, restart service, put dbs online