[lxc-devel] Question regarding an upstart job /etc/init/lxc-net.conf

[Adam Ryczkowski]

>> Dear Serge,
>>
>> I have a problem with reloading `dnsmasq` configuration for the
>> default lxc bridged network. Specifically, the `sudo service lxc-net
>> restart` does not force the dnsmasq service to re-read its
>> configuration.
>>
>> I can see why: the upstart script that is credited to you, does not
>> attempt to re-load the dnsmasq, if the bridge still exists.
>>
>> I want to try to fix this problem, so I read the
>> upstart_coockbook.pdf by cannonical. I learned there, that the
>> intended stanza where the service should be invoked is
>> `script/exec`, not `pre-start`. The `pre-start` is specifically
>> described as "Clearing out cache/tmp dirs is a good idea, but any
>> heavy logic is discouraged, as Upstart job files should read like
>> configuration files, not so much like complicated software".
>>
>> Can you tell me, why did you use the `pre-start` stanza to do the
>> actual job, living the `script` stanza empty?
>>
>> I'll be very grateful for your input. I if understand the logic
>> behind this script, I can be able to contribute to its development.
>>
>> Yours,
>>
>> Adam Ryczkowski
> If we were going to redesign the upstart job, I'd suggest thinking
> about how to break it up into pieces - the dnsmasq one as you say
> can be a normal job with dnsmasq in the script;  it starts on started
> lxc-net which creates the bridge, and stops on stopping lxc-net.
> A third applies the firewall rules.
Dear Serge,

I have impression this is actually very tough to do - I checked, that 
the dnsmasq doesn't conform to the PID expectation of the upstart - it 
doesn't work with either "expect daemon", "expect fork" or no expect 
stanza. It does provide its own PID, but I understand, that there is no 
means of telling this information to the upstart. (And maybe that's why 
the `dnsmasq` (as installed by apt-get install dnsmasq) uses the old 
/etc/init.d script rather then upstart.)

I know that I can wrap everything in my own scripts, but that defeats 
the purpose of upstart. Is there any "upstart-compatible" solution for 
services that are incompatible with "expect" stanza, but do provide 
their own PID file?


Adam