If you are not connected to the Internet for time synchronization, that is best fixed with hardware clock.
You will have to run the procedure prescribed on each Pi once, to enable network boot.
You do are using a normal WIRED Ethernet connection?
Code: Select all
git clone --depth 1 git://roy.marples.name/dhcpcd.git cd dhcpcd ./configure make sudo make install
See it also goes up, down and up for me, but does add the IPv6 for me, even on Pi 4.