balenaOS on RPI 3B+ need to assign docker a macvlan (DHCP) that is visible on local network

Product support balenaOS
1

I need to create 3 separate docker containers (with alpine) and I need the network interface to be accessible from the local network (same as host, but DHCP and individual interaces on each, not all like when using --net=host) can someone help me accomplish this?

Thanks! :+1:

EDIT:

On my RPI build (Raspbian) I was creating 3 macvlans

ip link add link eth0 name eth0.1 address xx:xx:xx:xx:xx:xx type macvlan
ip link add link eth0 name eth0.2 address xx:xx:xx:xx:xx:xx type macvlan
ip link add link eth0 name eth0.3 address xx:xx:xx:xx:xx:xx type macvlan

But when I created my containers and assiged --net=eth0.0 I get a network not found error.

2

Hello @edgararroyo

I don’t think that’s how docker’s --net= option works.

I’ve never done this before and I have no idea if it will work. I’m not sure this is supported on Balena.

Docker macvlan docs: https://docs.docker.com/v17.09/engine/userguide/networking/get-started-macvlan/
docker-compose networking docs: https://docs.docker.com/compose/networking/

a docker-compose.yml file like this might work (not tested):

version: "3"
services:
  service1:
    build: ./service1
    networks:
      - network1
  service2:
    build: ./service2
    networks:
      - network2
  service3:
    build: ./service3
    networks:
      - network3
networks:
  network1:
    driver: macvlan
    driver_opts:
      parent: "eth0"
  network2:
    driver: macvlan
    driver_opts:
      parent: "eth0"
  network3:
    driver: macvlan
    driver_opts:
      parent: "eth0"
7

Thank you for your response. I ended up doing this on Raspbian, but I need a balenaOS solution still.

# Get IPv4 for Gateway, Subnet Mask and IP Addresses
while [ -z “$ip4” ]

do
ip4=“$(ip -o -4 addr list eth0 | awk ‘{print $4}’ | cut -d. -f1,2,3)”
done

# Create Docker network
docker network create -d macvlan --subnet=“$ip4.0/24” --gateway=“$ip4.1” -o parent=eth0 \
-o macvlan_mode=bridge eth0

# Run dockers
docker run -d --name=‘alpine1’ --net=‘eth0’ --ip=“$ip4.101” ‘alpine’ tail -f /dev/null
docker run -d --name=‘alpine2’ --net=‘eth0’ --ip=“$ip4.102” ‘alpine’ tail -f /dev/null
docker run -d --name=‘alpine3’ --net=‘eth0’ --ip=“$ip4.103” ‘alpine’ tail -f /dev/null

Problem now is, if I use this RPI on another network that does not use subnet mask 0/24 and/or gateway .1 and/or ip addresses 101 thru 103, this will not work

Can I create a docker network macvlan that uses DHCP?

8

Hi,

I have done some quick testing and I do not think the macvlan plugin is supported in balena-engine. I have asked a collegue from the balena-engine team to comment though, as I may be mistaken.

18

@richbayliss ok, thanks. Also, can you find out if they can add the ipam dhcp driver?

Thanks again.

19

I don’t think it will be a case of adding them; we deliberately removed the plugin system from moby to reduce on-disk space usage. I am only unsure if this also included macvlan which is what I have asked for clarification of, but I would not expect that it would be desirable to add it back in.

21

Huh… Ok, thanks.

26

Hi, I can confirm that macvlan is intentionally removed from balenaEngine https://github.com/balena-os/balena-libnetwork/commit/9e7c869176ffe3131c65506747e361d6ba7ca2de

28

Is it possible to re-add in a custom build @lucianbuzzo ? I have need of it.

31

Hi there,

If you wish to roll your own version of balenaOS with a patched balenaEngine, you can find instructions on hacking on balenaEngine here (https://github.com/balena-os/balena-engine/tree/master/hack) and building custom images here (https://www.balena.io/os/docs/custom-build/).

We also offer custom board support plans which may better suit you, you can reach out to our sales folks directly if you are interested (https://www.balena.io/contact-sales).

36

Thanks. Sorry for not seeing this sooner. I’ll give it a shot. :smiley:

37

Hi guys, I came to this thread when I was looking about macvlan support on BalenaOS.
Has this situation changed in the past few months or there are still no plans for this plugin to be already baked in on the images that Balena provides?
Thanks!

42

Hi @Olivia

Welcome to forums!

The situation is still the same, there are unfortunately no plans at this stage for adding macvlan to balenaEngine.

Kind regards
Alida