Some ironclad rules for maintaining computer backups
As promised, this week I’ve got some tips to help you back up your Mac correctly — advice obtained over my three decades as a Mac troubleshooter, consultant and author.
Here are my two ironclad rules (and an axiom) for backing up:
Rule 1: One backup is better than no backup (but not enough).
If you have no backups, one is better than none, but if you want to be confident you can restore everything you need to go on with life and work, you need at least two complete backups.
Rule 2: At least one of your backups should be stored offsite.
If you keep your only backup in the same room (or building) as your Mac, any natural disaster or theft could wipe both of them out and leave you with nothing. Axiom: Make a bootable clone and update it daily.
The reason it’s an axiom and not a rule is that it only applies if you use your Mac to earn your daily bread and can’t be without it for a day or longer if disaster strikes.
Moving right along, the reason one backup isn’t enough is that stuff happens. A backup could become corrupted, be stolen, die in a disk crash or power surge, or suffer another fate that renders it useless.
Furthermore, at least one backup should be kept offsite—somewhere other than where your Mac is, just in case.
I recommend Time Machine as your first line of defense. It comes with your Mac, is easy to use and configure, and mostly reliable. All you need is an external hard or solidstate drive larger than your boot disk. And you can connect additional disks to create additional Time Machine backups. Your Mac will then back up to each disk in turn, round-robin style.
Because I need my Mac to work, I also maintain a clone backup using Carbon Copy Cloner ($39.99; www.bombich.com).
Each morning at 2 AM, it creates a bootable clone of my startup disk. So, should my boot drive become inoperable, I can boot from the clone and get back to work in mere minutes.
Finally, I maintain two offsite backups.
The first (updated monthly) uses Carbon Copy Cloner with an external USB drive stored in my safe deposit box.
The second uses Backblaze (www.backblaze.com), a commercial cloud-based backup service I’ve used for years.
It’s easy to set up and use and has worked flawlessly (albeit more slowly than local backups) for many years. I consider unlimited storage for my Mac a bargain at $6 a month (or $60 a year).
There is one last thing: A backup that doesn’t work is not a backup at all. So, test your backups — make sure they contain all of the files you expect and that you can restore files from them.