Just to add some info on guest agent here:
the guest agent does not set up the primary interface
there should be no race between guest agent and cloud-init for the primary interface
the guest agent does not start any dhclient process for primary interface, and should not care if any dhclient process on the system is killed
so a number of comments in this bug such as 'killing dhclient leaves guest agent dead' are not true
Just to add some info on guest agent here:
the guest agent does not set up the primary interface
there should be no race between guest agent and cloud-init for the primary interface
the guest agent does not start any dhclient process for primary interface, and should not care if any dhclient process on the system is killed
so a number of comments in this bug such as 'killing dhclient leaves guest agent dead' are not true