Differences between rvm and rdiff-backup.
rvm uses hardlinks and rsync to save backups. So if all but 5 files stay the same, only 5 files are backed up. It creates a directory by date - so you can do a simple copy to restore the files.
rdiff-backup just backs up the changed bytes, so its backups are generally much smaller. It also saves all permissions during each backup - even for different OS's.
Disadvantages of both:
rvm will backup until the partition is full and then delete from the oldest backup to allow it to finish. It does not currently have a feature to have it backup only so many days. etc. It also backs up the entire changed file, so its backups are generally larger than rdiff-backup.
rdiff-backup needs to rebuild the directory for restore and is a little less fault-tolerant if there was a prblem with the backup. It will fail and recreate from the last good one (usually the previous day) which means you can lose the differences for one day. It also takes much longer for the first backup as it builds checksums for all files when it starts that it uses to compare.
I actually use both, rdiff-backup on the same server on a second drive and rvm on a remote machine. I start rdiff-backup in the same cron job with cpbackup:
Code:
30 5 * * * /scripts/cpbackup ; /usr/bin/rdiff-backup -v5 --print-statistics /backup/cpbackup/daily/ /backup/history
so I get the report at the same time I get the cpbackup report.
Rvm I run on the other machine and it pulls. I actually run rvm manually as I have it on a spare machine at my home office, and do not have it powered on all the time. (Actually run it during the evening news.)
Note: I have not put a day limit in rdiff-backup yet (they have that option), as I am only at 48% of the backup partition and have backups since last year. I used to be at 85%+ with just daily weekly monthly. Since I only use that drive for backup - I am going to let it go and see how much it can actually hold.