Changing /etc/init/network-manager.conf as mentioned here did not fully solve the problem for me. Instead, it led to network-manager complaining about a missing messaging bus (DBus?) during shutdown (which was still too long ;) ).
The workaround mentioned in Bug 903825, however, seems to work perfectly. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/869635 Title: long delay at shutdown/reboot - network-manager doesn't close correctly To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/869635/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs