Mac Pro gets stuck in "safe mode" after Lion upgrade

Solution 1:

Boot to single user mode (Command-S) and see what fsck shows.

• /sbin/fsck -fy
• repeat the prior up to three times if needed

Assuming it boots, you can halt and then boot in verbose mode (Command-V) to restore all the console glory.

You can also peek at /private/var/log/system.log while on single user mode to see what was happening when the clock was passing faster than the gray progress bar.

Solution 2:

I was only able to solve this by doing a clean install of OSX Lion, then used Migration Assistant to copy over my data. Now I'm able to boot to safe mode successfully.

What forced me into doing the clean-install was that my Time Machine backups started failing. I don't know why, but it would fail repeatedly trying to copy the same files (I could cp -a them just fine on the command line). Looking at the system logs, it was the same files every time.

TM also failed to backup the system to my backup-backup TM drive (I alternate between two physical TM disks). It was only happy after I formatted one of the drives and started from scratch.

Here's what I did in detail:

1. Disabled Time Machine
2. Used Disk Utility to erase my TM drive (yes, I lost my historical backups).
3. Re-enabled Time Machine, set it to use the newly-formatted TM drive.
4. Let TM do a full Backup.
5. Booted using Lion installer on a USB key
6. Used Disk Utility to erase my Macintosh HD
7. Performed Lion install
8. Once booted to Lion, ran Migration Assistant to transfer my data from TM.

I'm really not happy about losing my older backups, but I needed a stable system more than I needed the old data.

This has been a really frustrating experience. I'm very careful about backups, yet every other release or so, OSX manages to trash them for me.