I am trying to set up an isolated lan using systemd-networkd on a RPi3B+ running Debian GNU/Linux 11 (bullseye) 64b. I followed the recipe here Workaround for a wifi bridge on a Raspberry Pi with proxy arp. The L3 bridge using parprouted is working using the subnetting procedure as expected when I have the wlan0 interface hooked to my home lan. My problem is when I try to enable the DHCP server on the RPi; then networkctl shows the DHCP server could not start because "Address already is use".
● 3: wlan0 Link File: n/a Network File: /etc/systemd/network/08-wifi.network Type: wlan State: routable (configured) Path: platform-3f300000.mmcnr Driver: brcmfmac HW Address: b8:27:eb:18:6b:5f (Raspberry Pi Foundation) MTU: 1500 (min: 68, max: 1500) QDisc: pfifo_fast IPv6 Address Generation Mode: eui64 WiFi access point: RPiGemini (00:00:00:00:00:00) Queue Length (Tx/Rx): 1/1 Address: 192.178.4.14 fe80::ba27:ebff:fe18:6b5f DHCP6 Client DUID: DUID-EN/Vendor:0000ab11db141ed8ce5dd9d00000 Offered DHCP leases: none Sep 18 05:12:35 raspberrypi systemd-networkd[174]: wlan0: Link UP Sep 18 05:12:36 raspberrypi systemd-networkd[174]: wlan0: Link DOWN Sep 18 05:12:36 raspberrypi systemd-networkd[174]: wlan0: Link UP Sep 18 05:12:36 raspberrypi systemd-networkd[174]: wlan0: Gained carrier Sep 18 05:12:36 raspberrypi systemd-networkd[174]: wlan0: Could not start DHCPv4 server instance: Address already in use Sep 18 05:12:38 raspberrypi systemd-networkd[174]: wlan0: Gained IPv6LL Would someone suggest how to proceed for further debug ? I am not clear on were the address conflict could be. Thank you for your time.
