I am currently trying to configure two Raspberry Pi 3s. The first one works fine. However, the other one always renames eth0 to eth1 on boot.
dmesg | grep eth [2.485760] smsc95xx 1-1-.1:1-0 eth0: register 'smsc95xx' at usb-3f980000.usb-1.1, smsc95xx USB 2.0 Ethernet, b8:27:eb:56:b6:06 [4.742863] smsc95xx 1-1.1:1.0 eth1: renamed from eth0 [4.794234] systemd-udevd: renamed network interface eth0 to eth1
Both Raspberrys have the same image on their SD card with minimum non-OS modifications in custom scripts (datalogging from sensors). Both SD cards' OS instances get their correct IPs (assigned by MAC) from the DHCP server when using the first Pi. Neither get any address when installed in the other Pi. Both Pis are new and from the same seller.
Changing eth0 to eth1 in /etc/network/interfaces works around the problem, but it took me hours to find out because I didn't expect the LAN port to NOT work out of the box. Something hardware-related seems to cause unnormal behaviour even though both Pis are the same generation.
Why does the hardware have such an effect on the OS and how can I fix it?