Just for fun I tried installing Stretch 9.1 on my Cubox-i4Pro. When it got to configuring the network via DHCP it failed to get any configuration info. I configured the network manually, and it was able to continue.
It appears that the ethernet interface is not getting initialized by the auto-configure part of the installer, but manual-configure part is properly initializing it. Before you ask, yes there is a DHCP server on the LAN, and it is found and does its job without fail for the very same client machine when booting installed Stretch — i.e. it only fails in the installer. Does anybody have a work-around that would allow me to avoid manual config? I have reported this as Debian installer bug # 866597, but nobody seems to have noticed yet. Enjoy! Rick

