Blag-o-matic

The 10.5.3 update crashed on me this morning and left my Mac Pro in a funny bit of broken.  I got a grey screen on boot and then nothing.  No Apple logo, no spinning wheel, nothing.  After about 10 minutes I got the globe icon (I think this says it’s looking for netboot servers).  Anyway, I got it fixed.

First I booted into Target Disk Mode and installed the combo updater from another Mac, although I’m not sure this was necessary.  I think the real trick was to hold down Option during boot to get into the boot chooser screen, and then wait.  After about 5 minutes it finally saw my hard drive.  I selected it and was able to boot.

After booting I checked with bless and sure enough, my boot settings were completely broken.  Reselecting my system volume from Startup Disk in System Preferences fixed it.  The take away is that on Intel Macs it seems that even without a valid boot image, given enough time the EFI boot loader will find it.