Outdated TYPO3 Version
This documentation refers to an outdated TYPO3 version - either select a supported version or make sure to use a TYPO3 Extended Long Term Support (ELTS) version to continue getting security updates.
More sophisticated backup strategies, such as incremental backups and distributed backups over several servers, geographically separated and rotating backups, etc. are also achievable but out of scope of this document.
Due to the fact that website backups contain sensitive information (backend user details, passwords, sometimes customer details, etc.) it is highly recommended to consider the secure encryption for these files.