Documentation "Use your Raspberry Pi as a network bridge"

[spicavirgo9]

I experienced a problem when following the instructions in
https://www.raspberrypi.com/documentati ... ork-bridge
using a RasPi4B with Bookworm in headless mode, connected with a ethernet cable to my internet-router.

After the command "sudo nmcli connection up Bridge" the bridge did not work. The cause was, that the device eth0 was still occupied by the usual "Wired connection 1" connection.
To make the bridge work, the command "sudo nmcli connection down 'Wired connection 1' " has to follow. If the connection to the Raspi used the Ethernet port (e.g. in headless mode or via ssh), this command will disrupt it and it has to be reestablished.

I would appreciate a update of the instructions on the above mentioned website.

[lurch]

I've never tried doing this myself, but if you're setting up a wireless bridge on your Pi (which will presumably involve configuring both the Ethernet and Wifi interfaces), it seems a bit "risky" to try doing that on a headless Pi, rather than with a monitor and keyboard temporarily attached? (because as you say, it's easy for any SSH connection to get disrupted) 🤔

[slain2]

Tested it using a headless Pi4 connected via Ethernet, Bookworm 64-bit. The Hotspot does not work until after a reboot (i.e. a mobile phone cannot connect to it.)
Before reboot: nmcli dev

DEVICE         TYPE      STATE                                  CONNECTION
eth0           ethernet  connected                              Wired connection 1
lo             loopback  connected (externally)                 lo
wlan0          wifi      connected                              Hotspot
bridge0        bridge    connecting (getting IP configuration)  Bridge

After reboot (phone connects OK):

nmcli dev
DEVICE         TYPE      STATE                   CONNECTION
bridge0        bridge    connected               Bridge
lo             loopback  connected (externally)  lo
eth0           ethernet  connected               Ethernet
wlan0          wifi      connected               Hotspot

posted same to Pi forum https://forums.raspberrypi.com/viewtopic.php?p=2277472#p2277472

[nathan-contino]

Thanks so much for this feedback. I'll get this fixed on the docs page ASAP. nmcli can be a tricky beast, I wonder what's changed since I originally wrote and tested this section?

Anyway, glad to hear you found a working solution. Even if the docs had an issue, at least we got you close enough to figure out the rest. Hopefully with this change the next user will have an even easier time.

[spicavirgo9]

Thanks for your comments. Glad to contribute a quantum to the RasPi community.

[spicavirgo9]

@nathan-contino Another hurdle I found in the instructions is: The password that was set for the hotspot gets erased by the command "sudo nmcli connection modify 'Hotspot' master bridge0".
That leads to an error message when activating the hotspot because of the now missing password.