Partial versus Complete Backups
Although the terms in question here are pretty descriptive, we will start with a few definitions. When we talk about a complete backup, we mean that the backup contains a copy of every file on the computer, and usually is bootable. Bootable means that the backup contains a complete working operating system that you could run on your computer. Everything else is a partial backup.
Complete backups seem, on the face, inarguably better. So why would anyone choose to go with partial backups? The main reason is that it’s somtimes just not necessary. Your operating system and other programs take up a lot of space, rarely change, and can easily be restored from installation CDs. Operating systems are also very fragile things. In many cases if you experience major hardware failure you will need to reload your operating system anyway. If you are keeping multiple versions of your backup (and you should be), complete backups can quickly become a hefty amount of data to store.
Even though complete backups aren’t always necessary, they are very powerful tools. If you do have catastrophic data loss, a complete backup can get your machine up and running in its previous working state in a matter of hours. If you have a lot of software that requires installation and configuration you could spend days getting it all set up again. Users for whom downtime is very expensive are the best candidates for a complete backup plan.
The best of both worlds
It’s very possible (and quite prudent!) to implement a hybrid strategy. A bi-monthly or weekly complete backup combined with a daily partial backup will keep you covered in most cases while keeping total backup size at a manageable level.
