Has anyone been doing remote (off-network) backups of their shared hosting servers via rsync? I am shopping for a backup server and trying to calculate how much bandwidth will I save when using rsync compared to regular ftp uploads. Any suggestions / statistical data are welcome . Thanks!
I think it depends on what you have on your server - how often files change etc.
I have syncer (from sf) which is a simpler version of rsync, its a .net windows program that grabs changed files and copies them over ftp. For us (running dotproject and mantis) instead of downloading MB of data, we end up copying 4 or 5 files a night (ones that have been added). Ok, it also copies the DB backup file in its entirely.
So.. for me, the bandwidth cost is the size of the MySql dump, plus a little bit extra. That's a reasonable starting point for you.
For shared hosting, I reckon you'll see about the same - the DB will change continually, 99% of files on the server will not.
For rsync, if you run the server-side rsync daemon, only the changes to each file will be copied so you'll see only a small part of the large sql dump transmitted, but this will be at a cost of CPU processing time.