I am looking if there is some guidance on being able to do automatic private IP (APIPA) in the scenario when a RPI3 device is connected directly over ethernet to a computer. If I plug in the PIs ethernet to my network then obviously I get assigned an IP address from the router which is great. I can then discover it using zeroconfig and get both an IPv4 and IPv6 address. If I plug the PIs ethernet directly into a computer, the PI gets no IPv4 address only its IPV6 address. I can still discover using avahi or using ping6 but I can not connect to a web server for example using a browser given the IPv6 address nor use its zeroconfig/bonjour address.
I would imagine this being a fairly typical scenario. Plug ethernet into router and get assigned an IPv4 address as well as plug directly to a computer and perform auto ip (169.254..).