Backing up does not affect the level of security of the system itself, but backup is crucial when, after a security crisis, there is a need to recover lost data. Sometimes, based on a backup, it is possible to determine the cause of the system crash by reconstructing security vulnerabilities or errors in the system. It is recommended to use an open-source backup system, such as UrBackup. When choosing, care should be taken that the backup system provides the ability to quickly and accurately restore data and that it is optimal, i.e. does not overload the server or storage resources.

A key recommendation to follow when it comes to backing up your data is the “3-2-1” rule: keep at least 3 copies of your data, make sure two copies are stored on separate devices or storage units and that one copy is stored off-site from the initial two copies, for example on a remote server.

Another important matter to take into consideration with backups is that although cloud storage providers (Proton Drive, Dropbox, Tresorit, etc.) are a common and safe solution to safely store data, they can be vulnerable to social engineering and similar attacks and do not guarantee that data will not be lost due to various reasons (e.g. Google Drive for desktop users reported losing months of data in late 2023). Taking this into account, making offline backups on an external hard drive or another computer is also encouraged as an additional precaution.