As documented recently, my Macbook Pro had a bit of an accident with a glass of beer the other week and I’m awaiting a replacement keyboard. The MacBook itself is out of warranty and I can do the switch myself for roughly £50. However, at the same time I thought I’d upgrade the internal drive, so I bought a larger SATA drive to fit.

I had some spare time last weekend so wanted to do the reinstall while life is a little quieter. However, the keyboard hadn’t arrived and I didn’t want to have to pull the MBP apart twice. I thus hit upon the idea of using the SATA drive with an external interface (this one from Maplin).

I connected it up to the MacBook (running 10.5.4) and it detected fine. Partitioned it for system installation and commenced a Leopard install from DVD media. So far so good. Once completed, I installed iWork ’08 and Logic Pro (the latter taking 6 hours to install – it does come on 7 DVDs!). Then came Apple System Update which attempted to install lots of things including the combo 10.5.4 update. Bear in mind the drive is running on USB still.

Reboot time. It sits, spinning its cog and showing the grey apple for, ooh, 3 hours. No response from the disk. Must have done something wrong, so I disconnect and reboot back to the internal disk. I download the 10.5.4 combo update and install manually to the SATA drive (still on USB, still recognising from my MacBook Pro running 10.5.4).

Reboot. Sits spinning again.

I start it into verbose mode (command-V on boot), which shows me that it ‘forgets’ the USB interface a little way into the boot sequence. Bugger. So it seems I have found a bug in 10.5.4 which happens only when booting from an external USB drive (if I plug it in when it’s booted from the internal disk it’s fine, and I can do what I want to the disk!).

There’s images documenting it here. If anyone with a little more Apple boot-fu than I have can offer advice that would be good. I’ve attempted without any other USB devices present and still get the same effect. I’ve not tried the disk internally yet, although it does check out fine under Disk Utility.