*** This bug is a duplicate of bug 1124803 *** https://bugs.launchpad.net/bugs/1124803
It turned out to a kind of mystery. No files are left open for writing but device is busy and can not be cleanly remounted readonly. Moreover it is not clear how to reproduce the issue. Concerning the formalities, since the issue addressed in the last comments have nothing with bug lp: #1124803 "NetworkManager doesn't respond to SIGTERM in daemon mode", the link to that bug might be removed. On the other hand original description of this bug fitted quite well to bug lp: #1124803 and it has nothing common with removing of network-manager, plymouth, etc. In my opinion the case with no bunch of packages should be filed as a dedicated bug with clear statements concerning conditions and ruled out hypotheses. Alexander, actually I can not figure out which way debug scripts can block umount, but since they provide no useful info, it is interesting what would happen if you completely remove debug scripts and temporally set HALT=halt in /etc/default/halt to have time to inspect last messages without writing them to a file. Have you tried memtest on that box? Have you experienced kernel panic or Oops due to kernel modules or hangs due to e.g. graphics card driver? Concerning the bug lp: #1124803, there are tails of modem-manager and so network-manager again. I can not comment on plymouth hangs since removing of "quiet" and "splash" from GRUB_CMDLINE_LINUX_DEFAULT works like a charm for me. (Actually I have tried an upstart task with "/bin/plymouth hide-splash" command before.) To obtain more debug info I would suggest to run sudo initctl log-priority info before shutdown (perhaps 'sudo sysctl kernel.printk="7 4 1 7"' to see the messages on the screen as well) and add dmesg > /upstart-messages.log to /etc/init.d/umountroot There is an issue with network manager proliferated to plenty of bugs, but it can be easily fixed. The problem with busy / when no processes are left and no files are open is very strange. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1073433 Title: Ext4 corruption associated with shutdown of Ubuntu 12.10 To manage notifications about this bug go to: https://bugs.launchpad.net/upstart/+bug/1073433/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs