I've found a solution to this bug for me (the reporter) so if problems still remain it may be a good idea to open a new bug for your problem.
Main problem: reboot/shutdown hangs with either "acpid: exiting" or "nm- system-settings: SCPlugin-Ifupdown: devices removed (udi: /or/freedesktop/Hal/devices/net..." and nothing can persuade the compute to complete side from a hard power cycle Primary cause (for me): nfs mounts in nested folders (i.e. /mnt/remote1/remote2) Solution: move nfs mount locations to non-nested folders (i.e. /mnt/remote1, /mnt/remote2) Further detail: Essentially my /etc/fstab mounts two remote filesystems in the following manner: mount remote1 to /mnt/remote1, then mount remote2 to /mnt/remote1/remote2. This works fine as long as the first nfs filesystem has a remote2 directory. However, on shutdown or reboot when unmounting the system tries to unmount /mnt/remote1 and fails because /mnt/remote1/remote2 is still mounted. Then it unmounts /mnt/remote1/remote2 which succeeds but it never attempts to unmount /mnt/remote1 again and thus we're left hanging waiting for all filesystems to be unmounted. I hope this sheds some light on the problem for others. This doesn't so much seem to be a bug as it is a misunderstanding about how (not) to mount network filesystems. I will be removing the binary package hint since this has nothing to do with acpid. ** Description changed: - Binary package hint: acpid - After reports and resolutions for many similar bugs (bug #288863, bug #126140, and bug #274995) none of those bugs or their resolutions have fixed the hang experienced during shutdown and reboot in Intrepid Ibex beginning near kernel release 2.6.27-5. On occasion after Splashy times out or by pressing ctrl-alt-F7 or ctrl- alt-F8 I will see "acpid: exiting..." with a flashing cursor and no activity. No amount of waiting ever allows the shutdown/restart process to complete, only a hard reset or shutdown is successful. Description: Ubuntu 8.10 Release: 8.10 acpid: Installed: 1.0.6-9ubuntu4 Candidate: 1.0.6-9ubuntu4 Version table: *** 1.0.6-9ubuntu4 0 500 http://ubuntu.media.mit.edu intrepid/main Packages 100 /var/lib/dpkg/status uname -a Linux lightyear 2.6.27-10-generic #1 SMP Fri Nov 21 19:19:18 UTC 2008 x86_64 GNU/Linux -- jaunty and intrepid shutdown/restart hang on "acpid: exiting" https://bugs.launchpad.net/bugs/302452 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs