from my days as an IT consultant specializing in Information Risk Management (some of the stuff we used to preach turns out to be true - who knew?)
- You MUST maintain, at a minimum, three copies of your data
- You MUST back up to different media (back then it was disk, tape, and optical)
- You MUST back up to different locations
- You MUST test your backups!
- You should, for efficiency, divide your data into stuff you can re-create, stuff you can't (easily) re-create, and stuff you don't care about, and play your backups accordingly.
That last part may not be as important as it was 15 years ago, storage has gotten dirt cheap. I don't fret over the difference between the three categories as much as I used to, but I still pay attention.
In practical terms, and my strategy is constantly evolving, my current scheme includes:
- Regular "image" copies of my OS & Apps drive - regularly being defined as whenever I make a major change, or once a month, and if I don't I can re-install everything, but I do not look forward to that!
- Regular file by file copies of my samples drives - as above I could re-install the libraries if I had to, but with most libraries being downloads it is not as simple as when they all came on physical media, and at 1TB I really don't look forward to that task, so I try to back it up every month as a whole - I think incremental backups for a 1TB drive don't make a lot of sense since so little changes, and if I had to go through several backups to get everything I'd be better off starting from scratch.
- Daily (and by daily I mean any day I work in the studio - sadly there are days when I don't) incremental backups of my data drives. This includes all my projects, not just music projects. These backups are made to a pair of 4TB USB3 external drives that get swapped. Both are in the house, but only one is ever in the studio.
- I don't have a solution for downloaded installers yet - for now they get backed up as part of #3 above. I need to do better!
I also keep a copy of all my data files in the cloud - I use several services because I can't fit everything into my 1TB Dropbox account any longer. I also backup my work laptop and my wife's laptop to the cloud.
If I had the time and money I'd like to trim this down to the same timetable, but everything gets backed up to a NAS device that lives in my home, and is mirrored to another NAS device somewhere off site, maybe a commercial cloud offering, maybe not.
The key, for me, is three copies (the computer itself. a local backup drive, and a remote backup).