Hang trying to enter single-user mode (runlevel 1)

[jimav]

Binary package hint: upstart

"telinit 1" causes a hang. The root shell prompt never appears. The screen is left showing the boot/shutdown splash.

To reproduce:
1. Log into a Gnome Classic (no acceleration) session.
    Make sure root has a valid password (run 'sudo passwd root')
2. Ctl-Alt-F1 to switch to a VT (in VirtualBox, press HostKey+F1)
3. In the VT, log in as root
4. telinit 1

Results:
The purple "Ubuntu" boot/shutdown splash screen appears, the dots advance for a while, then stop with all dots white.
Nothing else happens.

I suspect that the upstart scripts are forgetting to remove the shutdown spash screen, and so I can't see the console prompt (just a guess).

NOTE: I'm running in a VirtualBox VM. I need to enter single-user mode to remount the root fs read-only, to prepare to run "zerofree" (which zeroes unused blocks, allowing the VM's disk image file to be compressed during backups...)

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: upstart 0.6.7-4
ProcVersionSignature: Ubuntu 2.6.37-12.26-generic 2.6.37
Uname: Linux 2.6.37-12-generic x86_64
Architecture: amd64
Date: Wed Jan 19 13:49:50 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha amd64 (20101202)
ProcEnviron:
 LANGUAGE=en_US.UTF-8:en
 LANG=en_US.UTF-8
 LC_MESSAGES=en_AG.utf8
 SHELL=/bin/bash
SourcePackage: upstart

[john (john-l-montes)]

I'm seeing the same issue with ubuntu 12.04 and 14.04, cant get to a command prompt to perform single-user maintenance.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Bruno Nova (brunonova)]

I also discovered this issue (or something similar) in Ubuntu 14.04.
This is an old bug, but I will comment here instead of reporting a new bug.

When I run "sudo shutdown now" or "sudo telinit 1" to go to single-user mode, the Plymouth splashscreen appears briefly, but then a black screen appears with no text (there should be a root console there).
The root console is there however, but invisible, because typing "telinit 2" blindly and then pressing <Enter> returns the system to the normal mode.

If I disable the splashscreen (by removing the "splash" kernel parameter from the GRUB menu), switching to single-user mode works correctly. So, this is definitely a bug in Plymouth!
I can't reproduce this bug is an VirtualBox VM, however (maybe Plymouth doesn't work correctly there).
I must say that I'm using a laptop with Optimus graphics (using bumblebee). Don't know if that could have anything to do with this bug.

Booting into recovery mode works fine.

Another problem: switching to single-user mode kills all the consoles (tty1-tty6), but returning to normal mode doesn't restart them (lightdm is restarted correctly). I think this could be a very big problem on a server.

(I copy-pasted this comment from a similar bug report.)