How to pull docker image in a pure IPv6 host?

Docker Hub does NOT support IPv6!!!!!

In Dec 2020, docker hub only supports IPv4, and that's sad!

$ docker pull nginx

Using default tag: latest

Error response from daemon: Get https://registry-1.docker.io/v2/: dial tcp 52.4.20.24:443: connect: network is unreachable

But I need to pull images from docker hub, what should I do?

Proxy!

Yes, all we need is a HTTP proxy. Basically, I setup a HTTP proxy in another DUAL stack host (a host with both IPv4&IPv6), and ask the docker to use it.

HOW-TO

1. install proxy

I use goproxy. Download, extract, start proxy. By default, it listens on 33080.

$ ./proxy http --debug

--debug is for verbose information, drop it if everything goes well.

2. tell docker to use the proxy

$ sudo systemctl edit docker.service

and add the following to the file..

[Service]

Environment="HTTP_PROXY=http://[Dualstack_IPv6]:33080"

Environment="HTTPS_PROXY=https://[Dualstack_IPv6]:33080"

# reload to read the changes

$ sudo systemctl daemon-reload

# restart docker

$ sudo systemctl restart docker

# here we go!

$ docker pull nginx

PS, make sure nginx is listening on IPv6.

listen  [::]:80    #you need this line!

listen  80  # this listens on IPv4.

Reference

https://github.com/docker/roadmap/issues/89

(Yes, I am dawnfantasy)