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+This container provides fully automated SSL containers in IPv6
+networks
+
+## Requirements
+
+You need to have docker configured to use IPv6. The following code can
+be placed in /etc/docker/daemon.json:
+
+```
+{
+  "ipv6": true,
+  "fixed-cidr-v6": "2001:db8::/64"
+}
+```
+
+You need to replace "2001:db8::/64" with your own IPv6 network.
+
+Read more about [enabling IPv6 in docker](https://ungleich.ch/u/blog/how-to-enable-ipv6-in-docker/).
+
+## How it works
+
+IPv6 addresses are globally reachable, so IPv6 based containers can be
+reached from anywhere in the world.
+
+This container uses the domain **has-a.name**, which gives a
+name to every IPv6 address.
+
+Checkout how
+[has-a.name](https://ungleich.ch/u/blog/has-a-name-for-every-ipv6-address/) works.
+
+## How to use
+
+Start the container and use the logs to gets its domain name:
+
+```
+id=$(docker run -d ungleich/nginx-letsencrypt-ipv6)
+docker logs ${id} 2>/dev/null | grep "^Getting certificate"
+Getting certificate for 2a0a-e5c1-0111-0777-0000-0242-ac11-0004.has-a.name
+```
+
+With this information, you can now connect to your container:
+```
+% curl https://2a0a-e5c1-0111-0777-0000-0242-ac11-0004.has-a.name
+Welcome to 2a0a-e5c1-0111-0777-0000-0242-ac11-0004.has-a.name running with IPv6+LetsEncrypt
+```
+
+## How to extend it
+
+TBD