[pQd]

borg is great. we've been using it for the past 3 years to archive hundreds of file-level backups of servers, database dumps and VM images. average size of each borg repo is few GB but there are few outliers up to few hundreds of GB. most of backups are done daily, with 7-24 past days preserved in borg archive. borg repos are verified, copied to external disks, verified again and rotated offline each week.

borg replaced https://rdiff-backup.net/ for us and gave: * nice speedup of backups/backup tests, * decent saving in the disk space thanks to compression and deduplication, * decreased backup replication time [ borg repo tends to have much less, larger files compared to rdiff which has in its repo at least as many files as your source data; rsync likes it ].

to finish backups in a reasonable time we had to parallelize backup gathering [ each server / vm goes to separate borg repo; this limits a failure domain in case of corrupted repo, but denies us benefit of deduplication on larger scale - across servers ] and borg archiving. without that - we would be a limited by a single cpu core performance [ borg is not multithreaded yet ].

it's worth testing the backups - we're doing it each day by using borg's repo self test and by extracting few key files and checking their checksums and content... just in case.

echoing other comments - https://kopia.io/ looks interesting but we have not tried it yet.