Historically I’ve been pretty poor at keeping backups of my data. Recently however I’ve become aware of the need to be more vigilant in this area. Touch wood I have never suffered a disk failure on any computer I’ve owned, so I reckon I’m overdue one. The fact that my iMac disk now contains the results of months spent ripping my CD collection as well as a growing library of photographs it is time to take it seriously.
For the past few months I’ve been using the excellent SuperDuper! to perform backups of the iMac. However although the software is good I didn’t set up a scheduled backup so it relied on me to remember to run it regularly. Secondly the backup was performed to a Lacie 500GB Big Disk Extreme. Whilst this is an excellent external disk and runs very fast over Firewire 800, it is actually two 250GB disks arranged in a RAID 0 configuration. RAID 0 means that the two disks combine together and data is striped over them. This makes read and write access faster than a single disk, but has a big potential problem when the disk is used for backup, namely that if one disk fails then you lose all your data. Effectively you are doubling your risk of a hardware failure. Not ideal.
With the arrival of OS X 10.5 Leopard and the built in Time Machine backup I’ve decided to sort out my backup solution in a proper fashion. Therefore I’ve just ordered one of these beauties:
The Lacie 2big Triple is a 1TB triple interface (USB2, Firewire 400 and Firewire 800) drive. Like the extreme it actually contains two 500GB drives that make up the total capacity. The difference however is that this one supports RAID 1 as well. RAID 1 puts the disks in mirror mode, meaning that they both contain a copy of the same data. Thus, if one disk fails the other one is still there to serve your data. What’s more the drives are hot-swappable so you can replace the failed one and it will spin the new one up and copy everything onto it to bring it in line. In fact the disks can work in four modes: the aforementioned RAID 0 and RAID 1, plus JBOD which allows both disks to act as separate volumes, and Big which just creates a single volume without RAID support.
A couple of years ago consumer level (read affordable) hot-swappable RAID arrays were unheard of, so I’m really looking forward to throwing Time Machine at this beast. Unfortunately for the time being I’ll probably have to leave my Adobe Lightroom catalog out of the backup until the Leopard compatible fixes are available later this month. In the meantime I’ll back all my photos up to the old Lacie.
Of course, any comprehensive backup strategy will include offsite storage, afterall if the flat burns down or we get broken into then I could lose the iMac and the backed up data. I’m not yet sure what the best way to go with offsite is. Either buy a cheaper 500GB external disk and run a SuperDuper backup onto it every now and then and take it into the office to store, or try online storage with something like Amazon S3 or even .Mac. The latter is probably more reliable as I can script it to happen without needing to remember to bring a disk home every so often. I need to work out if it is cost effective for the 300GB or so of data which I need to have backed up.