Depends on the sort of backup you require.
If you're talking about a backup where you can restore individual courses, then Moodle is capable of doing that via a scheduled task and automatic backup or by backing up the individual course as a zip file. I however found problems with the automatic backup when it comes to Scorm package content and/or LARGE courses, they tend to overrun and then cause everything that comes after to skip.
The school I work at however also uses Microsoft Data Protection Manager (MSDPM) because we are entirely a Windows base and the DPM agent backs up the entire server on a file basis which is scheduled for every night, so in the event of a total crash I can restore Moodle completely in one restore from DPM.
So I rely on MSDPM for my site backup and then do individual courses as and when required.