In the bigger offices I care for, I use 4 different backup strategies, but any or all can and have failed before. Generally this stratagee includes one or more redundant backups for each server. The backup simply makes a daily data copy of everything, which resides on another server. The backup skips files which haven't changed since the last backup. As a result, after the first run, the backup is comparatively fast. In addition, another copy of data kept on external drives which are cycled in and out of the building and used primarily for off-site and disaster recovery related storage. Depending on the nature of the data being stored and the capability of the backup, the task can be very complex. As example, a site such as this has processes which are almost always running. This means that several critical files are not generally able to be backed up. The common solution is to pick a time to shut off all the services related to the forum, run the backup and then turn the services back on. Another but far less common solution is an agreement between the product vendor and backup or OS vendor(s) to make it possible for the backup to start and stop services to permit selected files to be backed up. In turn, the need to take stuff off line for a while puts pressure on the fastest backup media available. For this reason i long ago abandoned all streaming media.
The Lacie big disk genre is one of the best values for high volume & high speed storage: Plus their smaller capacity drives are a bargain.
http://www.lacie.com/products/product.htm?pid=10351
http://www.lacie.com/products/product.htm?pid=10600
http://www.lacie.com/products/product.htm?pid=10458
One thing about storage devices is that you want at least 2 of ‘em. Everyone that hasn’t been bitten assumes a backup will be there indefinitely. As a result, folks put things on one of em to store them indefinitely, but the backup media tends to fail at the worst time, and unless you have 2 you are planning for a nightmare like dead end. Worse, the cost to have a data recovery center pry a TB of stuff off a dead drive is enough to notch up the federal deficit. The cost of recovery makes the cost of a couple of drives thrifty by comparison.
Lastly the hardest part of this process is data verification. Generally I ask 2 or 3 folks a week to name something they've worked on. I'll then see if it made it to the backup. This is even more cumbersome with sites such as this one as the only real way to verify is to restore the content to
another computer and test. That kind of task is the typical budget breaker but still far less costly than
rebuilding from scratch.
Edit: Oh yeah, if you want an excellent and dirt cheap backup program look for one called xxcopy. It has crptic instructions but they have a great support site and unmatched flexibility