I do something similar, except I do a backup of a slave so as to keep the dump from blocking..

You may want to shop around to see what other people are charging. I used Bqinternet (http://www.bqinternet.com/backup/) for my backup services when i required them, and it was A+ for a low price.

Thanks for that link, that looks like quite a good service.

It doesn't look bad, although I only see daily backups. Doesn't appear to cover hourly, weekly or monthly.. Could just be me.. In fact, it only appears to have one backup.. The daily one..

The samba share feature is a good idea (provided it is read only).. However, I could see people abusing the "No data transfer limit" feature in combination with the share. You could basically use the share to serve large files (i.e. videos).

Why pay money when you can do it yourself, like the pro's?
Just use rsync, it is the only method that will not break your busy servers while doing a backup.
What do you think they use when they do your backup? Heh...

Edit: Check what bqinternet.com uses as procedure.
Features:
Daily backup using rsync technology
SSH encryption
On-the-fly compression
Get back online instantly with a Samba mount
FTP access
No data transfer limit
No setup fee

If you peruse the mods forum, you can see how technically apt your average Vbulletin owner is. Asking them to handle rsync would be an interesting follow..

If the average vBulletin owner is not capable to perform a rsync process, then the above listed service will come handy to them.
However, you have to look at rsync process like you would copy files from a folder to another... really easy. Setting up your own local rsync mirror is just a matter of configuring the rsyncd daemon to make your portage directory available for syncing. That's all. :)

Backing up however needs to be more than just mirroring the site. Lets say, for whatever reason, config.php is wiped out, or corrupted. The mirror server will just copy it, or delete it I suppose. Or a file gets hacked, it will get copied to the mirror.

By using incremental backups with hard linking, you can keep snapshots on the backup server to allow for rollbacks to certain times (hourly, daily, weekly, monthly)..

I guess what I am saying, is rsync alone is not all that helpful.

this thread is in the big boards forum.