Raspbian Lite strech 4.19.40-v7+ on Pi 3+ eth0 not added to bridge on boot

Question

After following "thousands" of guides I'm about to giving up on it.

Intended setup: wifi access point with builtin wlan of Pi3. So a bridge of eth0 and wlan0.

• interface names are eth0 and wlan0 (raspi-config config option used)
• dhcpcd.conf uses denyinterfaces eth0 wlan0
• sysctl.conf has ip_forward enabled
• hostapd is configured to work on br0
• /etc/network/interface.d/bridge.conf sets eth0 and wlan0 to manual and br0 to dhcp and adds eth0 and wlan0

The setup works flawlessly until I reboot. After the reboot eth0 is not part of br0 anymore. (brctl addif br0 eth0 is neccessary as well as a dhclient call.)

What do I do wrong that the configuration is not applied correctly during boot?

Thanks a lot for any help.

Answer 1

You are using an experimental kernel and presumably firmware, probably from running rpi-update. There are outstanding issues with the 4.19 kernel.

"In normal circumstances there is NEVER a need to run rpi-update as it always gets you to the leading edge firmware and kernel and because that may be a testing version it could leave your RPi unbootable". https://www.raspberrypi.org/forums/viewtopic.php?p=916911#p916911 Even the rpi-update documentation now warns "Even on Raspbian you should only use this with a good reason. This gets you the latest bleeding edge kernel/firmware."

sudo apt-get update; sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel will put it back to the latest supported kernel/bootcode.