How would your own backup script differ from that of Cpanel using Incremental mode (rsync)?
Well incremental backups will use less resources but I've never been keen on these from the perspective of full backups being faster to restore from if required.
I was comparing cPanel's full backup (which backs up each account in it's own archive along with lots of unrequired elements) to different scripts which make full backups (allowing full server or account restores to be made). Some other scripts are much quicker, can have more options with regard to remote storage etc and consume less total space.
The script we use wasn't custom written. The base version can actually be found here: http://www.rfxnetworks.com/sysbk.php. To work with that script we have custom written backup management (remove old backups, keep required ones) and restore scripts added to it.
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