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A layered backup scheme

With the advent of Mac OS 10.5 Leopard, backup is now easier than it’s ever been. Using Time Machine is a simple process: you’re asked if you want to use it on an external disk as soon as the disk mounts. You choose ‘Yes.’ Then, you choose which folders to exclude from the backup (which is not very intuitive — you have to add folders to subtract them from the back up). At any rate, that’s about it. You’re done. The only thing you have to remember to do, if you’re using an external drive, is to turn it on (that’s if you don’t leave your computer and external drives on when not in use to save power). That’s nice. That’s easy. Time Machine, as you likely know, allows you to go back in time to recover lost files. This is a welcome addition to my backup scheme.

But it’s not the end-all of backup for two reasons:  it’s not a bootable clone and the backup is stored on a local drive either inside or next to your primary mac. The bootable part is important if you want to be able to keep on working if your primary drive dies. Having your most critical data stored somewhere other than home is important because fires, floods, and terrible things can happen.

Here are a few additional steps (in addition to using Time Machine)  I take to keep me covered for almost any scenario. First, I ensure I always have a bootable clone. I use SuperDuper, the popular little backup app that allows you to make an exact mirror copy of your primary drive. Because SuperDuper makes your backup bootable, and because it’s an exact replica of your drive, you can keep on working if your main drive dies. (note that SuperDuper is not yet Leopard-ready as of the time of this post)

If you have more than one mac in your home, the bootable backup is even handier. Say that you have to send your iMac in to get repaired after a hard drive failure. It’s gone for two weeks. But, during this time, you need to keep working with the applications and files that were on that computer. No problem. All you need to do is plug in your external drive to one of your other macs and boot up from that drive (Preferences: Startup Disk). It’s not going to be as fast as using your primary mac, and the cloned copy might be a few days old … but, trust me, it beats the alternative. Alternatively, if you’re in the middle of some critical work that you must finish and you don’t have a second mac, a bootable clone allows you to keep on working on that machine. When you’re done, then you can send in your imac for repair. Of course, if you have a macpro, then you probably have more than one internal drive and you can fix your dead drive all by yourself. The key to backup, of course, is frequency and consistency. You need to do it often and on a set schedule.

That’s why I paid for SuperDuper instead of using the free built-in Disk Utility or the free Carbon Copy Cloner. It has a ‘Smart Update’ feature. Those other two do the job well, but the don’t have this feature. This means that SuperDuper only replaces what is needed to make your backup identical to your source disk. you’ll appreciate this feature immediately if you have a lot of data. For me, it means each backup takes about 15 minutes for 120GB of data. A full Not-Smart update, by contrast, can easily take an hour or more. As an aside, SuperDuper is popular for other reasons as well: it is beautifully and thoughtfully designed, it does one thing and does it extremely well, and the application’s instructions and explanations are very easy to understand. And do you know why it’s called ‘SuperDuper?’ It only occurred to me yesterday that the Duper is short for Duplicate. That may have been obvious to others, but it only just occurred to me. Now let’s just hope the SuperDuper team get the Leopard-ready version of their software working very soon.

So, now you have Time Machine and SuperDuper. Should you put them both on the same drive? Not if you can help it — you can easily do this with disk partitions, but if that one disk goes, you’re going to lose the whole disk … not just one partition. Having said that, I did place my SuperDuper and Time Machine backups on the same drive. My reasoning? I never worried about having only one disk when I only used SuperDuper … so I’ll take my chances and place them on the same disk. The odds of that disk and the internal drive of my iMac both dying simultaneously are, I like to think, pretty remote. I am using a 500GB Lacie d2 Quadra with two partitions. For SuperDuper, I alloted 200GB. My iMac drive is 230GB. I figure if I get up to 200GB of data on this disk, it’ll either be time to think about archiving some stuff or deleting some apps/files … or it’ll be about time for a new mac. So 200GB is big enough. I used the rest of the disk space for my Time Machine partition. Instead of using Time Machine to back up the entirety of my iMac internal drive, I only set it to back up the user folders. This setting should give me a lot of space to go pretty far back in time for my files only. For the apps, if I have to restore them, I’ll use my SuperDuper clone.

But what happens if you have a fire, flood, theft, etc. and you lose your external drive backups and your mac? You’re screwed. Unless, that is, you employ some sort of off-site backup scheme. While there are now a slew of online companies which offer external backup locations for your stuff (for a modest monthly fee), you may ask yourself if this is secure. (There is a good wrap-up of current services in the December 2007 issue of MacWorld, by the way). It very well may be secure and I’m sure this is a viable option, but I haven’t ventured to try this yet. My current solution is a bit convoluted, but I think it keeps my data pretty well distributed. My main off-site strategy is this: I bought a tiny little 160GB Iomega external drive. Not only is it quite small, but it purportedly has some patented bump-and-drop protection built in, which can’t hurt. I back up all documents and photos from all my macs onto this drive using the free SilverKeeper backup software — just the things I absolutely, positively would be devastated to lose in a worse-case scenario. I then take this disk off-site and store it securely at work. You might also consider storing it in a fireproof/waterproof safe at home, but I’m not crazy about that idea. In the case of a fire, this safe could get quite hot. While the papers inside may not mind, I think a hard drive would. You might also consider storing it with a trusted friend or family. Note that I don’t back up my iTunes library to it — it’s huge … and it’s already backed up to my iPod (always with me) and my Time Machine and SuperDuper clone.

Finally, I employ a few odds-and-ends backups. I use a simple automator script to ‘sync’ calendar, address book and mail to an external server where I host my websites. This Lifehacker.com post will show you the basic idea. If you subscribe to .Mac or use a different synching application, this wouldn’t be necessary. But this is a cheaper way to go and it gets the job done. I also selectively backup some files to my gmail account (you could also use an external server for this) just for convenience – my wife’s Rapidweaver backup, for instance, and some writing projects that I may want quick access to on the go.

So, putting it all together, this scheme isn’t too complicated. Time Machine
is automatic. SuperDuper clones are automatically scheduled for every other day (or will be, once the shareware is Leopard certified). Automator synching is manually done once a week (I just need to click a button to sync — Chronosync might also be an easier way to do this. I’ve heard great things about it, but I don’t have any experience using it). Once a month, I update my off-site Iomega disk. This certainly isn’t the easiest methodology, and I’m sure it’s not the best methodology, but hopefully it will give you some points to consider to develop your own backup scheme.

  1. Just wondering . . . how much longer are you going to wait before updating to Leopard?

  2. Good question, Manju. I have upgraded to Leopard. I didn’t wait as long as I originally planned. I’ll post on my experiences so far with Leopard very soon!

  3. Good info. Just after you posted this, Carbon Copy Cloner released version 3 which adds support for synchronization and scheduling. It is also a Universal binary and Leopard ready!

  4. Yeah, I just heard that this week. I installed it, but couldn’t use it. I am cloning 125 GB of data to partition of 200 GB. SuperDuper had no problem with this, but CCC says there’s not enough space on the destination disk for a full clone. I don’t get it.

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