The reason mcollective is started despite /etc/init/mcollective.override is present is that in some circumstances it may happen that cron may start nailgun-agent BEFORE cloudinit reconfigures mcollective. In this case nailgun-agent doesn't find "identity" field in mcollective config, tries to write something there and then restart mcollective.
The reason mcollective is started despite /etc/init/ mcollective. override is present is that in some circumstances it may happen that cron may start nailgun-agent BEFORE cloudinit reconfigures mcollective. In this case nailgun-agent doesn't find "identity" field in mcollective config, tries to write something there and then restart mcollective.