Unable to boot to recovery mode after problematic High Sierra upgrade

Question

After an upgrade to high sierra, my 2013 mac pro experienced intermittent freezes that required hard restarts to resolve. On every restart I get a black screen with a progress bar, and there is an empty progress bar under the launch pad in the dock (see images).

okay, so something is messed up and after trying to fix it for a while I figured a full OS reinstall was in order. However, when I try to restart into recovery mode using either command-r or option key during start-up, the restart procedure continues as if I hadn't pressed the keys. I can successfully trigger a pram flush using command-pr on start-up, so it doesn't appear to be a keyboard issue at first glance. I've disconnected everything from the computer except the monitor, keyboard, mouse and ethernet.

diskutil confirms that I have a recovery partition:

$ diskutil list
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                 Apple_APFS Container disk1         1.0 TB     disk0s2

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +1.0 TB     disk1
                                 Physical Store disk0s2
   1:                APFS Volume Macintosh HD            646.0 GB   disk1s1
   2:                APFS Volume Preboot                 31.0 MB    disk1s2
   3:                APFS Volume Recovery                506.6 MB   disk1s3
   4:                APFS Volume VM                      2.1 GB     disk1s4

/dev/disk2 (disk image):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        +3.0 TB     disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:                  Apple_HFS Time Machine Backups    3.0 TB     disk2s2

Is there any other way to get to recovery?

Answer 1

When macOS' recovery partition fails, it creates a Catch-22 situation where you need the patient to be able to be able to perform brain surgery on itself.

If you have a ≥ 8gb usb drive you can erase handy, you can use it to create a recovery drive which you can use to diagnose and (one hopes) repair your intractable Mac drive(s). It'll have all the same tools recovery mode offers: you can test, run first aid, or perform other related functions without being dependent on the disk you're trying to repair.

1. Choose  > App Store… and download the High Sierra installer if /Applications/Install macOS High Sierra doesn't already exist.

2. When the download completes, the installer will open automatically. Quit it.

3. Edit the following command, removing any returns to make one long line. Replace YourDriveName with your USB drive name.

   sudo "/Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia" --volume "/Volumes/YourDriveName" --applicationpath "/Applications/Install macOS High Sierra.app" --nointeraction

4. Open /Applications/Utilities/Terminal.

5. Copy/paste the above command at the terminal prompt, press return, and enter your password.

6. After the process completes (it'll take awhile - be patient), restart your computer and immediately press and hold option. This will eventually display the startup disk picker, from which you can choose the recovery drive you created rather than your normal start disk. That'll at least give you a reliable work space unaffected by whatever's wrong with your drive.