Today I learned that FRITZ!Boxes have an IPv4 link-local fallback address, in case a device doesn’t catch any DHCP configuration. According to the documentation a FRITZ!Box is also always reachable through
169.254.1.1. So if you device is ever configured using auto-IP and assigns itself an IP address from the IP range
169.254.0.0/16, you can easily reach your FRITZ!Box and enable DHCP, without the need to configure a static IP address.
I came across this after reading w4tsn’s article about his IoT Fallback IP setup and thought that the
169.254.0.0/16 IPv4 range would fit better for such a configuration. Some quick research if/how others might implement it, made FRITZ!Boxes show up.