How to implement a full backup strategy

2nd June, 2010


Backing up your data is not a glamorous part of running a business, but it might just save your arse one day. I recently overhauled my entire backup policy to give Shark Attack full belt-and-braces protection. I thought I’d break it down here for anyone who is wondering where to start.  (This details a Mac-based solution but, whilst the choice of software may vary, the same principles apply to any computer setup).

We shall be using…

My backup strategy needs to provide me with comprehensive disaster recovery for the following:

  • My Macbook Pro’s internal hard disk (200 GB)
  • My external ‘Resources’ hard drive (750 GB)

To do this I use two hard drives:
A 2TB hard drive for on-site backups, divided up into volumes as follows:

  1. 1700 GB for Time Machine (backing up both the MBP and the ‘Resources’ external drive and going back as far as available storage will allow)
  2. 250 GB for a clone of the MBP’s hard disk (plus breathing room during the process)
  3. 50 GB for an Emergency Room
  4. 10 GB as my Photoshop scratch disk (irrelevant to this discussion)

And a 1TB external portable hard drive for off-site backups divided up as follows:

  1. 250 GB for a clone of the MBP hard disk
  2. 750 GB for a clone of the Resources drive

1. Use what you already have—Time Machine

With the advent of Max OS X 10.5 (Leopard) Apple introduced what I consider to the the most useful refinement to the OS for many, many years: Time Machine. Suddenly, the process of backing up your data was built right into the system; all you had to do was plug in an external hard drive and say “use this one, please”. Bam! Automatic, incremental backups on the hour, every hour.

Most of the times that I need to call on Time Machine are not the traditional ‘hard drive failure/threw away a vital file by accident’ events. The fact is that drive failures, though ultimately inevitable, are not daily occurances, and I am normally sensible/OCD enough not to throw away vital files. But sometimes something just goes wrong. A typical example is a hardware driver becoming corrupted. Last time that happened it was my Wacom driver. No problem; I simply went into Time Machine and pulled back the driver file from a month or two previously when I knew it had been working just fine. That alone probably saved me 45-60 minutes of working time.

So, if you use a Mac running 10.5 or later and you are not using Time Machine then you really need to set it up. DO IT NOW! Finished? Okay, let’s proceed.

2. Send in the clones

The Time Machine system has one failing, and that is that it is not directly bootable (you can restore from Time Machine if you boot from your Mac’s installer disc, but this is a kludgy workaround). If something in the operating system is stopping your mac from booting properly, or if you’ve dropped your laptop and the disk itself is damaged, what you want is a clone: a byte-for-byte copy of your mac’s main drive that you can use as an alternative startup disk.

For this reason I always keep a partition available for making a clone using Shirt Pocket Software’s indispensable SuperDuper! application. This partition, ideally, should not be a partition on your startup disk, because if the cause of your woes is disk damage then it won’t be able to help you; mine sits on the same drive as my Time Machine backup. Additionally, if your Mac’s internal drive has more than one partition then you’ll want to set up an equivalent clone partition for each.

Also, don’t make the clone partition the same size as the volume that it is backing up, especially if the source volume is getting full; for reasons of safety when updating your clone backup SuperDuper! needs to copy files before it deletes the outdated ones and so often both files need to exist on the clone simultaneously. If the file is very large and you haven’t allowed some breathing room, this can cause SuperDuper! to run out of room and the backup will fail. I built an extra 50 GB into my partition just to make sure.

3. The Emergency Room

The last thing I added to my on-site disk is not really a backup, but it’s nice to have: a smallish partition containing a stripped-down, bare-bones install of Mac OS X, with my favourite disk repair/diagnosis apps added. Currently this means Drive Genius, Tech Tool Pro and Disk Utility, but as soon as I get around to updating Disk Warrior I will be adding that back into the mix because it’s never let me down yet (their upgrade policy, however, insists that I mail my existing Boot CD back to the USA, so I keep putting it off).

The reason for having the Emergency Room partition is that if I need to diagnose a problem I don’t necessarily want to boot from my clone—since the clone is an exact copy of the main drive this can have side effects such as my email app opening on login and deleting mail from the server when I don’t want it to, so it’s better to have a volume set aside specifically for ‘booting from’ when a bit of digital surgery is needed.

4. Offsite backups

The final part of this all-bases-covered strategy is the oft-neglected off-site backup, a fact that was brought home to me 9 months ago when my office flooded. Additionally, my insurance company (the excellent Blyth Valley) told me that insurance firms very much like you to have off-site backups, and that if you can show that you’d taken every reasonable precaution to safeguard your data it’ll help your claim to go through that much more easily.

To solve the off-site problem I looked initially at online services, and the best of the bunch (without straying into the crazy-expensive realm of enterprise solutions) seemed to be Backblaze. However, the initial upload was the problem. To my mind a backup, whether onsite or off, should backup everything. Some basic maths told me that this would mean an initial upload time of… um… let’s see… carry the one… six months. Of non-stop data transmission.


Clearly I was going to have to forego the luxury of automated, behind the scenes backups over the internet and opt for the more prosaic hard drive option. I bought a 1TB Western Digital portable drive and divvied it up into two suitably-sized volumes, then used SuperDuper! to clone onto it copies of both my MBP’s hard disk and my Resources hard drive. Then I stuck it in my bag. When I leave the office, it leaves with me. Fire and flood no longer hold any fear for me (well, not with regard to my data, anyway) just as long as I remember to update the clones on the portable drive every so often.


And that is that. A full belt-and-braces backup strategy, some of which requires a minimal effort and some of which entirely takes care of itself. If you don’t already have a backup policy in place then perhaps you will see enough similarities between my requirements and your own to be able to use at least some of the above as a kind of starting point or template. Because, let’s face it, none of us want to end up as a cautionary tale.

Filed in…


Selected work

Latest blog entries


Monthly archives

Copyright © 1999-2017 Shark Attack. All rights reserved.