[lug] Debugging a startup problem

[Jed S. Baer]

Hi Folks.

Running Mint 17.3 here, which means it's an odd mashup of Upstart and
some legacy SysV init. There's a few pieces of systemd here too, but
Upstart is controlling the init process.

Symptom is that on a reboot, the network doesn't come up for about a half
hour. I haven't yet repeated the experiment, because it's working now. :)
Once the system is up, ifconfig shows me just the lo interface, and the
network manager, invoked as root, has everything greyed out, which I take
to mean that it can't find anything on which to operate. So, I guess the
whole networking subsystem failed to start. Until later, after which,
it's just fine. Nothing being reported in the nightly logwatch run.

But, at some point, I'll have to shut this box down, and try to see
what's happening. I have nothing to go on. I looked at everything that
seemed remotely relevant in /var/log, and found no error messages.
Nothing helpful in dmesg either. So, I'm looking for an incantation or
two to try and pin this down. So far, I've come up with:
  initclt list | grep net
and see what's stopped/waiting, and then ... wave a rubber chicken around?

But it seems as if networking is hung at boot, waiting for something to
happen, which eventually happens. Issuing /etc/init.d/networking restart
had no effect, and produced no output.

I now have a 2nd symptom, perhaps unrelated. My front USB ports have
stopped working, so I'm starting to suspect the MOBO is going south. I'd
test the USB ports on the back, but they're filled with dust bunnies.
(Yeah, I can get behind there with a pipe cleaner, but I need to shut
this thing down and clean elsewhere too.)

Any suggestions appreciated.