On a Ubuntu 22.04 machine using the boinc/client image, I'm not able to connect to the instance remotely.
I've used the same image on other machines on my home network and I can connect to all of them from my main (windows) machine using the BOINC Manager.

Once docker-compose starts the container, I can see it's written some of the config files to the mapped folder, so I know it's running fine. However, trying to connect to the instance via BOINC Manager, it shows Connecting to [IP] in the status bar and never connects. With the other machines it connected immediately and asked to connect to projects.

First I thought it might be the firewall on the machine blocking the port, so found that it was 31416, allowed it in ufw - no joy.

I then installed the linuxserver image lscr.io/linuxserver/boinc:latest which works fine, but to connect to it I have to use the browser, which is not ideal. I want to be able to stack all the manager windows for all machines on the network on one of the screens, so this kind of spoils the symmetry. :)

docker-compose.yml is the standard one listed on https://hub.docker.com/r/boinc/client and https://github.com/BOINC/boinc-client-docker.
If I try to map the port 31416 on the container, docker complains, but I think the

network_mode: host

should deal with it anyway.

I'd appreciate any suggestions as to how to even begin diagnosing this?


My docker-compose.yml section:

  boinc:
    image: boinc/client
    container_name: boinc
    restart: always
    network_mode: host
    pid: host
    volumes:
      - /opt/appdata/boinc:/var/lib/boinc
    environment:
      - BOINC_GUI_RPC_PASSWORD=123
      - BOINC_CMD_LINE_OPTIONS=--allow_remote_gui_rpc