[Docker Version, IPv6] Failed to obtain IP Addresses!

[SamuelBorn]

Hello @mietzen, thank you for your awesome project!

I am hosting a home server with IPv6 and encountered troubles with the docker version of this project.

Running sudo docker-compose up with the following docker-compose.yml on my Raspberry Pi

version: "3"
services:
  porkbun-ddns:
    image: "mietzen/porkbun-ddns:latest"
    container_name: porkbun-ddns
    environment:
      DOMAIN: "..." 
      SECRETAPIKEY: "..." 
      APIKEY: "..."
      FRITZBOX: "192.168.178.1" 
      SLEEP: "300" 
      IPV4: "FALSE"
      IPV6: "TRUE"
    restart: unless-stopped

I get the following error:

me@raspberrypi:~/porkbun $ sudo docker-compose up
Recreating porkbun-ddns ... done
Attaching to porkbun-ddns
porkbun-ddns    | Traceback (most recent call last):
porkbun-ddns    |   File "/entrypoint.py", line 65, in <module>
porkbun-ddns    | 2024-01-16 18:33:27,785 WARNING  Can't reach IPv6 Address! Check IPv6 connectivity!
porkbun-ddns    |     porkbun_ddns.update_records()
porkbun-ddns    |   File "/usr/local/lib/python3.12/site-packages/porkbun_ddns-0.5.0-py3.12.egg/porkbun_ddns/porkbun_ddns.py", line 142, in update_records
porkbun-ddns    |   File "/usr/local/lib/python3.12/site-packages/porkbun_ddns-0.5.0-py3.12.egg/porkbun_ddns/porkbun_ddns.py", line 102, in get_public_ips
porkbun-ddns    | porkbun_ddns.porkbun_ddns.PorkbunDDNS_Error: Failed to obtain IP Addresses!

I have verified that running the programm with IPv4 works (but is useless for me due to DS-Lite)

      IPV4: "FALSE"
      IPV6: "TRUE"

Do you have an Idea on how to fix the problem?

[mietzen]

I never tried ipv6 in docker and I'm not entirely sure that this makes sense. You would have to enable IPv6 in docker: https://docs.docker.com/config/daemon/ipv6/

But even then I would guess that the DNS Record would point to the Porkbun container. Using IPv6 inside docker only makes sense with the --public-ips option and a static ipv6 address.

If you got a DS-Lite connection you would have to run porkbun-ddns (python version) in the same VM / Host / LXC-Container as the service (e.g. nginx) you want to expose, at least that would be my understanding.

You could also build your own docker container with nginx and porkbun-ddns and enable IPv6, but I guess when you want to stick with docker it would be way easier to use caddy with the dynamic_dns module.

[SamuelBorn]

I already had IPv6 enabled for docker (the default bridge) so this most likely is not issue.
I am unfortunately also no networking expert, so I am no huge help in this regard.

For now I am just using the pure python version of the project - which runs fine.

Maybe flag the IPv6 option of the Docker container as experimental or something like that for now.

[mietzen]

Maybe flag the IPv6 option of the Docker container as experimental or something like that for now.

👍 I'll added to the docs. I'll also have a look at this the next days, the main problem seems to be that urllib.request.urlopen('https://v6.ident.me').read().decode('utf8') fails with a URLError, so https://v6.ident.me might not be reachable, so my first guess was that IPv6 isn't enabled.

[mietzen]

This is a docker-compose problem:

https://forums.docker.com/t/solution-docker-ipv6-and-docker-compose-woes/97852

docker run works flawlessly:

$ docker run -e DOMAIN="my-domain.de" -e SUBDOMAINS="abs,asw" -e SECRETAPIKEY="xxx" -e APIKEY="xxx" -e IPV4="False" -e IPV6="True" -it mietzen/porkbun-ddns:latest     
2024-01-17 04:54:29,673 INFO     AAAA-Record of abs.my-domain.de is up to date!
2024-01-17 04:54:31,190 INFO     AAAA-Record of asw.my-domain.de is up to date!
2024-01-17 04:54:31,190 INFO     Sleeping... 300s```

[SamuelBorn]

Yep, verified it on my machine. Docker run works.
Thank you.