This is going to be a quick, poorly written post. I want to get this information out there since this might only be a short lived problem for mac users.
I have a 2017 iMac with a SSD.
I was running 10.13.2.
I did the supplemental update for meltdown and spectre.
The iMac would not boot.
I booted into recovery mode to run “First aid”. It exited with error 11.
I booted into single user mode and ran fsck_afps. Same error 11.
I made a disk image of my drive as a secondary backup to my time machine backup.
I did a reinstall of the OS. It still would not boot.
I tried with disk utility to erase the Macintosh HD. This is when things really went sideways.
I thought I would do a network restore of the OS, it would not work!
I downloaded the full 5+ gb installer of High Sierra. I created a bootable USB installer. That would not work. I could get the installer to boot, but not install.
It gets a little fuzzy in my memory at this point. While booted to the USB installer, the iMac would shutdown to a black screen and just generally thrashed as I tried to create a new Macintosh HD volume with the Disk Utility application. I could not truly clear the ssd.
I had to resort to terminal diskutil to really blow away everything.
With diskutil I created the new volume.
Now I was able to install the OS.
I tried to used to migration assistant, and the computer would shutdown just like earlier. I did this twice.
I tried to restore my DMG, that failed when i tried to scan for restore.
I wiped and installed the OS again. This time I created a new admin user and completed setup without migration assistant.
I go to do software update, and find out that the new download of High Sierra did not include the supplemental update.
I download that and restart. The supplemental install took about 20 minutes.
With all updates done, and a fresh admin user. I was finally able to use migration assistant and bring the user accounts back from my time machine backup.
WHAT A RIDE!