I have a box running at DigitalOcean with Ubuntu 12.04
It's rare that my system will boot or takes forever - normally it just hangs / chokes. A reboot from a remote shell used to be pretty quick and I could reconnect within 10 seconds or so. Here's screens shots of where it gets to:
I have been told that such may happen after a kernel upgrade if their "hypervisor" doesn't have that kernel and that it may require manual setting from DO's support.
I had them mount their ArchLinux recovery disk and checked out the system's /lib/modules: I've been told these are the supported kernels that Ubuntu can run with.
I set my kernel to: ubuntu 12.04 x64 vmlinux-3.8.0-42-generic From DO's droplet settings.
I'm still getting the above hangs and some of the images above were after such.
fsck
from the recovery mode on the root partition to make sure its fs is in consistent state.