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Some CMS have a built-in backup options, or have plugins which can make backups. We recommend against using such tools.
While backup plugins look easy to use, they often involve running extremely complex PHP code to generate the backups. These backup scripts frequently break down because of file size limits or PHP execution time limits, leading to incomplete or corrupt backups. They also generate a high server load when creating or restoring backups, which may cause other problems for your website.
And even if the backup scripts completes successfully, you may run into similar issues when restoring the backup, which may result in you having a backup you can’t restore anywhere.
This is why you should not use backup tools and plugins, and always create backups with FTP and phpMyAdmin.