Diagnosing power cycle vs software reboot

[Nikhil Nair]

Hi Colin,

On Fri, 11 Nov 2016, Colin Law wrote:

> [...]
> If you look in /var/log/syslog then for a controlled reboot you will see messages indicating the system is shutting down
> (services stopping and so on), then messages indicating it is booting.  For a power down the messages will simply stop, there
> will be no shutting down messages.  Then the boot messages will appear.

Thanks, I would have expected that, but hadn't found any shutdown
messages.  After I read your message, I took another look, and there was
one I'd missed - rsyslogd shutting down after receiving signal 15.  No
other messages about services shutting down, however: there was a gap of
over a minute before that rsyslogd shutdown message, and a gap of about a
minute after it before the startup messages started.

Is that normal?

In any case, there was an rsyslogd shutdown message for my deliberate
reboot, but not for any of the other 4, so I guess that means it was a
power cycle issue after all.  Or, given that there was only one message in
the deliberate reboot case, is that inconclusive?

Cheers,

Nikhil.