Comment 4 for bug 1096531

James Hunt (jamesodhunt) wrote :

Investigation shows that this problem is only triggered by '/forcefsck': the actual problem results from jobs that satisfy both conditions below:

- *end* before /var/log/upstart/ becomes writeable.
- has spawned one or more processes that continue to run *after* the job has finished and after /var/log/upstart/
  has become writeable.

Problem is more reliably recreatable if a job such as the following is created:

start on startup
    # spawn a process quickly that allows the job itself to end fast,
    # but which also produces output after the job has finished.
    /bin/sh -c 'while :; do cat /etc/fstab; done' &

end script

On my test server system, the standard job that triggered the problem was network-interface: it calls ifup which spawns off dhclient which is still running after the network-interface instance job has finished.