Looking for a comprehensive guide to how (K)Ubuntu starts

[Ralf Mardorf]

Hi,

do yourself a favour and don't waste your time with learning to
understand how your Upstart based install works.

With Ubuntu 15.04 the default init system became systemd, before that it
was Upstart. While both are able to use SysV init scripts, it's not
worth learning all that runlevel stuff anymore.

Some distros don't need
https://www.freedesktop.org/software/systemd/man/systemd-sysv-generator.html
IOW they completely got rid of this "hybrid" approach.

What is "Kubuntu 14" for? Most likely it's not 14.10, but 14.04.x LTS.
If so, search the Ubuntu Wiki and help pages regarding informations
about do-release-upgrade and upgrade to the latest LTS release, that by
default does use systemd. Don't care about the SysV init scripts that
are still used, too, just care about systemd and try to learn how
this works.

Assuming you are still on 14.10, you perhaps could do a release upgrade
by more than one step.

Regards,
Ralf