Accessing static assigned host eth0 from inside a container

Product support balenaOS
1

I’ve got a Balena Fin v1.1 running pretty great. It’s connected to WAN using cellular and LAN using a static assigned IP address for eth0. Both the cellular and eth0 configs are done via the files in the system-connections folder and both interfaces are working as expected from the host.

My issue is that from the host I can ping devices that are connected to eth0, but I cannot access those same devices from within a running container. It seems that I simply cannot route traffic to the eth0 interface of the host from a container for some reason. Do I need to explicitly tell a container that it can access eth0? Is there some kind of conflict between the cellular network I’m using to connect to the internet and the LAN network my eth0 is connected to? The LAN has ALL staticly assigned devices, there is no DHCP server or router involved. Devices are connecting directly to each other and are in the same network. I can ping the connected device from eth0 from the host.

Here is the network manager config for eth0:

[connection]
id=my-ethernet
type=ethernet
interface-name=eth0
permissions=
secondaries=

[ethernet]
mac-address-blacklist=

[ipv4]
address1=192.168.13.31/24,192.168.12.1
dns=8.8.8.8;8.8.4.4;
dns-search=
method=manual

[ipv6]
addr-gen-mode=stable-privacy
dns-search=
method=auto

…and my network definition in the docker-compose file:

networks:
  default:    
    ipam:
      driver: default
      config:
        - subnet: 192.168.12.0/24

Any ideas for what I should try?

Again - The host is able to ping a device at 192.168.13.100 so I know the config on the host interface is working. The service inside my container is NOT able to ping that device.

Hopefully I am making a silly mistake!?

5

Hi, this looks like an issue described here. Can you help us to debug by doing what’s suggested in this answer?

7

I tracked this down to an isolated container network issue. All is working as it should, I’m just bad at networking. Whoops!

8

Hi,
glad to hear you were able to make it work, feel free to let us know if you have any other questions.