Good Friday for everyone, I come here to give you a hint of a sensational backup solution, the solution unlike the ones given by Lawrence is not Open Source, but it is one of the best in cost benefit that I found to date for bckup.
Comet Backup is a backup solution that works more or less like ArtBackup, Acronis, MSP360, among others, however the great advantage of it is the low cost of 2 dollars per agent per month and it works very well!
I have some partners who were using the Acronis solution for backup and spending 2 thousand dollars monthly, migrated to Comet Backup + Backblaze B2 and the value dropped to less than 1/3, maintaining the same quality of service.
I recommend that you take a look and do the 30-day tests, it is very worthwhile. https://cometbackup.com/