[Bug 1089771] Re: umount of /var partition fails during shutdown, due to lingering dhclient

[Clint Byrum]

Actually I don't think this is network-manager's fault. By all rights,
it should be *dead* by this point.

umountnfs.sh emits unmounted-remote-filesystems, which stops networking
(stop on umounted-remote-filesystems), which emits deconfiguring-
networking, which causes dbus to stop (stop on deconfiguring-
networking), which causes network-manager to stop (stop on stopping
dbus). So umountnfs.sh should not exit until network-manager (the
upstart job) is considered *stopped*. This means that NetworkManager
should be completely *dead*, even SIGKILL'd if it didn't die within 5
seconds.

/etc/init/networking.conf emits deconfiguring-networking in post-stop.
If I'm reading the upstart state machine properly, job_finished() is not
called until a job's state gets to JOB_WAITING, which would have to be
after the post-stop. However, its possible post-stop had an error, which
would still finish the stopping event for networking, but would not emit
deconfiguring-networking. So, verbose logging would confirm this by
showing that the networking post-stop failed.

If that shows true, I believe this would be resolved by changing dbus to

stop on stopping networking

** Package changed: network-manager (Ubuntu) => ifupdown (Ubuntu)

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ifupdown in Ubuntu.
https://bugs.launchpad.net/bugs/1089771

Title:
  umount of /var partition fails during shutdown, due to lingering
  dhclient

Status in “ifupdown” package in Ubuntu:
  New

Bug description:
  The 'Unmounting local filesystems...' stage of shutdown fails, and reports that the /var partition is busy.
  This occurs where /var is on its own separate partition.

  I am using 64 bit Kubuntu 12.10 (quantal) but I was also able to reproduce this problem on a clean install of
  xubuntu 12.10 i386 in virtualbox.

  I added debugging messages to the script: /etc/init.d/umountfs
  'fuser -m /var' shows that the only process with a file open on /var is dhclient, which has a dhcp lease file in /var/lib/dhcp/
  Using 'fuser -k -m /var' in the umountfs script kills the offending process, allowing for a clean shutdown,
  but that's not the right fix.

  I'm not sure how to proceed from here.
  dhclient is a child process of NetworkManager - should NetworkManager clean it up?
  the /etc/init.d/sendsigs script, which kills other processes during shutdown, is specifically blocked from killing dhclient
  by an entry in /run/sendsigs.omit.d/ so it is not clear to me what should be happening.

  Apologies if I filed this in the wrong place.

  Description:    Ubuntu 12.10
  Release:        12.10

  upstart:
    Installed: 1.5-0ubuntu9
    Candidate: 1.5-0ubuntu9
    Version table:
   *** 1.5-0ubuntu9 0
          500 http://jp.archive.ubuntu.com/ubuntu/ quantal/main amd64 Packages
          100 /var/lib/dpkg/status

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ifupdown/+bug/1089771/+subscriptions