How much disk space do encrypting file data and taking backups require?

If you enable encrypting file data at rest or backups on the M-Files server computer, it is essential that you ensure that there is enough disk space on the server computer at all times to accommodate encrypted file data and backup data.

Disk space needed for encrypting file data at rest

Encrypting file data at rest makes an encrypted copy of your file data while leaving the unenrypted file data temporarily in place, which essentially doubles the space needed for vault file data on the disk. Thus enabling encryption requires at least double the amount of disk space that your vault file data takes. You can specify the location of the vault file data with the database engine settings in the advanced properties of your vault.

After you have enabled encryption and ensured that your vault content is accessible, you must manually run the Optimize Database (Thorough) operation to remove the unencrypted file data of the vault. If the option Delete the files of destroyed objects is available, select it.

Note: Make sure that the optimization is not done between file data and metadata backups.
Note: The scheduled automatic optimization does not remove the unencrypted file data.

Disk space needed for backups

As a general rule of thumb, the server machine should always have at least an equal amount of free disk space as the overall disk space required for 1) the file data and metadata of your document vaults and 2) the server-specific data of the M-Files Server instance. However, it is highly recommended that you keep several backups of the vault and server data to give yourself several chances to recover data in the event of system failure or data loss. Therefore the recommended disk space needed for backups is dependent on the backup policy used in your organization.

For more comprehensive backup instructions, please see the M-Files knowledge base article M-Files Backup Policy.

Important: Do not back up an active M-Files system with a snapshot of the file system where its data is stored. This can create a damaged or unusable backup because write operations to files (most importantly, the database engine files) can be ongoing and, thus, incomplete. If you use full virtual machine (VM) snapshots for backups, make sure that the VM software fully supports creation of snapshots of an active system. This means that the software can restore the system to exactly the same state, including the memory and CPU states.