Having been a professional developer since the mid-1980's I have always been acutely aware of the need to take steps to protect my electronic data from accidental deletion, intentional deletion, intruders and all the other potential acts of God which fall under the control of Murphy's Law. I remember the CEO of the first company I worked for coming into our office one morning, squeezed my shoulder, grinned and stated "Ally, whatever you do, don't lose the source code". The warning has stayed with me ever since. [I also recall a colleague, some years later at a different organisation, who thought that photocopying source code listings was an effective backup mechanism!!]
In those days we weren't fortunate enough to have any of the amazing Configuration Management (CM) tools available to today's development teams. This was the dawn of the PC and electronic backup facilities were primitive, even in the corporate world. At home, a 10Mb hard drive cost a small fortune and was way beyond most people's wallets. So, we copied floppy disks, and made copies of the copies, and stored them at home and in the office to try and ensure some sort of data redundancy.
Despite the awesome advances in technology over the past 30 years, with highly sophisticated CM systems, amazing backup software like Time Machine, Carbon Copy Cloner (CCC) and SuperDuper, and the availability of cheap on-line and cloud based storage, Murphy's Law is still dominant. Something I was reminded of only too clearly last week.
While I'm in the Apple Harvest subsidiary office at my partner's house, I've had to rethink my backup regime. At HQ, with the iMac, I run Time Machine backups onto my 3Gb Time Capsule, copy my 1Tb iTunes library onto an external hard drive using ChronoSync which is scheduled to run on a daily basis (I also subscribe to iMatch under iTunes), and all my business files are synchronised with various cloud systems, like DropBox and SugarSync as well as my MacBook Air. Once a week I clone the hard drive using CCC.
Whilst at Mel's, using the MacBook Air, I set up a Seagate external Backup Plus drive to work as a Time Machine disk as well as the normal regime of cloud backups. Although I tried to set up a Time Machine link to the Time Capsule at HQ this proved unworkable. I keep my iTunes library on a second Seagate drive so this doesn't interfere with any TM backups.
But of course, this strategy failed to take into account Murphy's Law and last week the TM backup disk failed leaving me with an apparently dead drive and no backup facility; an accident waiting to happen. I managed to get a new Seagate disk ordered and delivered the following day and a couple of days later I fetched an additional drive from HQ. This is now configured to keep a CCC clone of the MBA internal flash drive and a second partition clones the 128Gb SD drive I use to extend the MBA storage capacity. These are now automatically incrementally cloned every day.
I still find it quite extraordinary that so many people fail to think about backups until it is too late. It seems that people fall into two main categories: those who never backup and those who have sophisticated strategies that allow for as many potential situations as possible. Even using Time Machine with no real thought is better than nothing, but you can still get caught out if your backup disk dies.
My recommendation for anyone without a backup strategy in place is to take an hour or so to seriously think about it, and put it in place. You need to think about the value of the data you store on your computer. If it's easily retrievable, or of little value to you, then maybe a simple Time Machine backup without a safety net is good enough for you.
If your whole life is stored on your computer and you cannot measure its value (no insurance claim can ever restore lost photos or videos once a disk is damaged beyond repair) then consider a backup strategy with multiple options. It'll be highly unlikely for everything to fail simultaneously, unless there's a massive electro-magnetic pulse which destroys all our global systems - in which case, rather than worrying about your computer, you're probably better off looking up at the sky to try and dodge the aeroplane which is just about to fall on you!