A Happy New Year to you all.
I have something of a disc drive and back-up obsession. My various computers all of have a number of external disc drives that are used for back up, or for holding my photo and music libraries. I must have at least a dozen external drives in all. My MacBook has an external drive that I use for a Time Machine backup and another that is used once a week with SuperDuper! to clone the internal hard drive. My Mac Mini which is now used only to serve up my permanent large music, film, TV show iTunes library has the iTunes library on an external drive which is also copied to a second drive together with another drive that is used for Time Machine and a SuperDuper! back up. My iMac until just before Christmas had three external drives: one for Time Machine, one that is holding a SuperDuper! clone back-up and the main photo libraries (and small iTunes library). Another drive held a copy of the photo libraries and iTunes library. In addition, I have a couple of portable drives that I use with the MacBook and a couple of other external drives that have been used for media with the MacMini. Most of these drives (other than the little portable ones) are multi-interface and I generally use the firewire to connect to my Macs.
It does become quite a challenge to make sure that all these drives that hold copies are updated regularly, although that is not too difficult as the iTunes library on the MacMini is pretty much static; it holds my classical CD collection that is mostly ripped from my own purchased CDs, together with a relatively small number of recordings purchased from iTunes and other classical digital download services. It also holds some TV programmes and films — mostly that have been downloaded from iTunes as a result of free promotions (typically from The Times/The Sunday Times in the UK or iTunes promotions like the 12 days of Christmas. Periodically, particularly after a new item has been added, I will re-copy the whole library. At some point I’ll get around to using an rsync based tool and a script to do it automatically at regular intervals. The Photo Library held on the iMac is also fairly easy to back up as the iPhoto libraries are now pretty much static as all my new work is stored in Aperture and Aperture has the concept of a vault which makes it easy to periodically (e.g. every time I import new photographs) update it from within Aperture.
Over the last couple of months the iMac had been behaving strangely where it would occasionally lock up. While the iMac is old (a 2006 model, that I really should replace with a new one that can run Lion), it hadn’t generally behaved in this sort of way. I would have to use the power button to turn off the iMac and then reboot it. Being the sort of person that I am, I would then normally use Disk Utility to verify the internal drive and all of the external drives connected at the time. As I’ve mentioned before, checking a Time Machine is not for the faint-hearted. A drive that has been used for some time will take a long time to check. I’m not sure quite what caused me to start thinking it might be an external drive problem — I don’t think I found anything in the logs, although I had noticed that often a Time Machine update was taking a long time (although on my iMac not a lot typically changes, other than the receipt of more mail messages). Anyway, the Time Machine hard drive (which had been used for some years) would not repair. Trying Disk Warrior also failed, and indeed the drive wasn’t even showing up at all some times that I tried connecting it. This was a shame as I really would have liked to have copied the contents to a new drive and continued the Time Machine sequence, but it wasn’t going to happen. When the Time Machine drive did show up on the machine, I could typically access most of the content but trying to do a complete copy to a new drive always failed.
Strangely a second drive on the iMac (used for a copy of the photo library) also started playing up at the same time, and so a new 3TB Western Digital drive was purchased (just at the time when prices seemed to be going up daily because of the floods in Thailand), to hold both a Time Machine backup and a copy of the libraries stored on the other external drive. Since installing the new drive, I’ve had no problems with the iMac locking up.
Fast forward a few weeks to earlier this week and I noticed that the Time Machine drive used with my MacBook wasn’t showing up on the MacBook. Indeed the drive didn’t seem to be on despite being plugged in to the mains. This particular Western Digital drive actually has an on-off button on the back which I’ve never been able to quite understand the logic for but pressing it briefly or for a longer time had no effect. However, using the power supply from one of the now retired failing drives caused it to spring in to life. So at least that wasn’t a drive failure — just a power supply failure. Strangely though, I had noticed that recently the MacBook would take a long time waking up from sleep (or at least it would appear to wake instantly, but then hang for some time before allowing one to type a password); however since replacing the power supply this seems to have got much less obvious. I know that FireWire is a technology that is very tightly coupled in to the machine and I wonder whether the failing power supply on the external drive had been causing some strange behaviour. All of this is consistent with the advice often given when trouble shooting to disconnect all external items.
As a result of all this, I’ve now replaced two external drives (although not necessarily the oldest). I still need to tidy up my process for ensuring that content primarily stored on external drives is always duplicated (and if necessary backed up to the cloud as well).