Almost just had a heart attack

[xanis]

I installed a couple updates (firmware, Java, etc.), rebooted, and got the dreaded flashing folder with a question mark on it. I tried a bunch of stuff in the linked KB article to no avail, and when I booted from my install USB, Disk Utility couldn't find my main hard drive. :'(

Rebooted again, nothing. Rebooted a second time... IT WAS BACK! WTF?

Fortunately I have a current Time Machine backup, so it wouldn't be the end of the world, but it would have been a pain in the ass. Does anyone have any idea why this would have happened? FWIW, this was the Java 1.7 update and SMC firmware update.

 

[Zaap]

99% likely due to the firmware update.

Firmware updates often cause the Mac to have to reboot several times, and sometimes with the flashing question mark. Makes perfect sense if the update is related in any way to the SATA controller. (It actually shouldn't be interrupted while it's updating the firmware-flashing question mark folder or not- and should reboot itself.) If you read the description of the update, it possibly will say that this might happen.

 

[xanis]

99% likely due to the firmware update.

Firmware updates often cause the Mac to have to reboot several times, and sometimes with the flashing question mark. Makes perfect sense if the update is related in any way to the SATA controller. (It actually shouldn't be interrupted while it's updating the firmware-flashing question mark folder or not- and should reboot itself.) If you read the description of the update, it possibly will say that this might happen.

I don't remember seeing anything about that, all I remember reading was that the fans would spin up to their full speed during the update. *shrug*

 

[Zaap]

I wouldn't fret too much unless it happens again. Since a firmware update tweaks hardware level settings, all sorts of side-effects (hopefully temporary) can happen. The fans would be due to the power management being disabled. The missing startup folder is just the Mac having temporary amnesia- either unable to see it's own SATA controller, or the PRAM could get temporarily corrupted making it forget the location of the startup disk. In either case, a few restarts might be required to get things running again. (Or in the old days, a PRAM zap- not sure if Macs need that anymore).

 

[xanis]

I wouldn't fret too much unless it happens again. Since a firmware update tweaks hardware level settings, all sorts of side-effects (hopefully temporary) can happen. The fans would be due to the power management being disabled. The missing startup folder is just the Mac having temporary amnesia- either unable to see it's own SATA controller, or the PRAM could get temporarily corrupted making it forget the location of the startup disk. In either case, a few restarts might be required to get things running again. (Or in the old days, a PRAM zap- not sure if Macs need that anymore).

Interesting, didn't know all that. Good to know for the future so I don't freak out again.