The GFS retention also helps you to mitigate risks that the short-term retention policy has, such as large number of subsequent incremental backups.
Depending on which flag is assigned to the full backup, it will be stored for specified number of weeks, months or years. These GFS flags can be of three types: weekly, monthly or yearly. For this purpose, Veeam Backup & Replication creates synthetic or active full backup files and marks them with GFS flags. The long-term or Grandfather-Father-Son (GFS) retention policy allows you to store VM backups for long periods of time - for weeks, months and years.
