/sbin/halt fails to halt system

[Gerben]

issuing the halt commando (e.g. halt as root) will not switch off the computer. All services will be stopped, a final ¨ * Will now halt"is posted on the console (a desktop installation), but the computer does not switch off. Either it needs to be switched off at the machine (physical machine) or a "Fore off"needs to be performed (kvm virtual) needs to be performed.

This happens when /sbin/halt is used.
When the (unity?) menu "Shut Down..." is used, the machine switches off as expected (either shut down from login-console when not logged on, or from (unity?) menu when logged on).

/sbin/reboot reboots the machine correctly.

See attached screenshot for graphical output.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: upstart 1.3-0ubuntu11
ProcVersionSignature: Ubuntu 3.0.0-17.30-generic 3.0.22
Uname: Linux 3.0.0-17-generic x86_64
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
Date: Sat Apr 7 12:50:22 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: upstart
UpgradeStatus: No upgrade log present (probably fresh install)

[Gerben (gerbgeus)]

The graphical output at the console (pressing 'esc' when shutting down).

Last lines read:
" * Will now halt"
"[ 38.922882] System halted."

[Launchpad Janitor (janitor)]

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

[eXtace (djandruczyk)]

Also affects me as well. On VMware ESX 3.5 using 12.04 AMD64 guests. It's worse on VMWare because the guest console won't show anything at that state, so it's hard to know if it REALLY halted or not aside from not pinging back on the network side.

[billy (miztadux)]

Same thing on ESX 3.5 and ESXi 4.1, using 12.04 amd64 with the open-vm-tools package.

Note that the vmware initiated shutdown ("Shut Down Guest" in Vi client) actually shuts down; and the last line displayed is "Power Down" (instead of "System Halted" when using halt).

[billy (miztadux)]

After carefully inspecting this issue this seems to be the expected behavior.

In normal runlevels "halt" just calls "shutdown -H now", which is supposed to simply halt the system without poweroff.
Alternatively the "poweroff" variant of the command calls "shutdown -P now", which actually powers off the machine.
(and halt -p is equivalent to poweroff)

From "man shutdown":
       -H Requests that the system be halted after it has been brought down.
       -P Requests that the system be powered off after it has been brought down.

From the reboot/halt/poweroff source:
  switch (mode) {
  case REBOOT:
   args[i++] = "-r";
   break;
  case HALT:
   args[i++] = "-h";
   args[i++] = "-H";
   break;
  case POWEROFF:
   args[i++] = "-h";
   args[i++] = "-P";
   break;
  }

I guess we just got used to systems that powered down when calling "halt" when they really shouldn't, but I have to say it's been a while since I encountered a system behaving differently...

PS: found some related links:
more info here: http://ubuntuforums.org/showthread.php?t=1968626
duplicate bug: https://bugs.launchpad.net/ubuntu/+source/upstart/+bug/991997