Comment 4 for bug 1061977

OK. So, heres a summary of the problem.

 * system boots with 'console=tty1 console=ttyS0'
 * system may not actually have a serial device (see mesg for more info)
 * kernel output does get to video console (and ttyS0 locations on systems where that is available)
 * all cloud-init jobs have 'console output', and some run successfully, but then one fails.
 * echo HI MOM | sudo tee /dev/console
    results in:
   tee: /dev/console: Input/output error
 * starting job afterwards as 'start cloud-init-final' will die immediately
   running the same thing it *would* run by hand (but with output not to /dev/console) will run to completion.

So it certainly seems to me that kernel assigned /dev/ttyS0 to /dev/console and upstarts' stdin and stdout there. and then later that device 'went bad'.

I was under the impression that kernel went through these and assigned /dev/console to the last valid entry, but it appears i may be wrong [1] on that.

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[1] http://www.kernel.org/doc/Documentation/serial-console.txt