We have a fibre connection at home and like most of the home setups, you will be assigned a new external IP address every time your router re-connects, or when your lease is renewed by your ISP (whenever they feel like it :-))

As we want to expose some of our internal server(s) [Docker containers] to the outside world, and be able to access it via a URL which we know, we’ve in the past opted to use The free version of allows for up to 3 hosts to be configured, on one of the domain names they offer – like (just an example).

If you want to use your OWN domain, then you need to purchase a PLUS DNS Management package.

ENTER – ! is a free service (running on AWS) which allows for the creation of known URLs linked to your dynamic IP address (similar to

You will typically get a URL like – BUT you can update that (via your domain registrar/DNS provider) to point to your own configuration – like

You still need to update your IP address with DuckDNS to make sure it has the latest IP address assigned to you and this is where the DuckDNS Docker container comes in handy.


Ok, after that long-winded intro here is how I configured the following domain – to point to a locally hosted WordPress container (running on Docker) and hosting my wife’s blog.

Step 1 – Setup a DuckDNS Account

Go to
Register to get access [Free]
Once registered, you will get an access token assigned to your account.
You can now also select to add a unique sub-domain to and link it to your account.
We added to my account.
screenshot 2019-01-05 at 16.16.34

You also have the option on this screen to manually update the external IP address assigned to you by your ISP.

You now have a URL ( which points your IP assigned to your router. (although at this point it probably won’t do anything as you still have to configure a couple of other things to make it all work)

Step 2 – Docker container for DuckDNS updates

As your IP address assigned to you by your ISP changes all the time, you need to let know about these changes to make sure that the IP on their side always resolves correctly to your environment.

Fortunately there is a docker container to assist with this.

Check to see the DuckDNS container maintained by the team [they do some AWESOME stuff ! – I’m using some other containers maintained by them and will cover this in later posts]

NOTE: I won’t go into how to get Docker installed in this post and assume you already have docker up and running.

So from the command line, I used the following to pull the latest DuckDNS container and creating it on Docker:

docker create –name=duckdns –restart unless-stopped \
-e TZ=Africa/Johannesburg \
-e SUBDOMAINS=greystormydesigns \
-e TOKEN=*******-****-****-****-***** \

Let’s unpack that a bit:

name = this is the name of your container for your own reference

–restart unless stopped = this tells docker to restart the container if something goes wrong, except if you specifically stopped it

-e TZ = sets the timezone

-e SUBDOMAINS= this is the important bit for DuckDNS – it let’s them know which domain you want to update – you only specify the 1st bit (

-e TOKEN= this needs to be your token assigned to your account when you registered

and then lastly the name of the container to pull from – linuxserver/duckdns

With all this done, the docker container should be created and ready to be run.

All you now have to do is run the container on docker and it will update the IP address on every 5 minutes.

A typical start-up log will look like this:

_ ()
| | ___ _ __
| | / __| | | / \
| | \__ \ | | | () |
|_| |___/ |_| \__/
Brought to you by
We gratefully accept donations at:
User uid: ***
User gid: ***
[cont-init.d] 10-adduser: exited 0.
[cont-init.d] 40-config: executing…
Retrieving subdomain and token from the environment variables
log will be output to docker log
Your IP was updated at Sat Jan 5 16:47:04 SAST 2019
[cont-init.d] 40-config: exited 0.
[cont-init.d] done.
[services.d] starting services
[services.d] done.

So that’s it – you now have a docker container running which updates your dynamic IP address on every 5 minutes.

We’re almost there – just a couple of small things to complete !

Step 3 – Update you router to allow for port-forwarding to your locally hosted website

Port-forwarding can be tricky (and risky), so please be careful with this setting if you’re not 100% sure what you’re doing. 🙂

I suggest you search google for instructions on configuring port-forwarding on your specific router.

Please note that most routers have this option and you would not have to buy anything …

I have an Asus Router and configured the port-forwarding on the WAN side – pointing to my internal server ( on port 8080.

So this rule routes all external port 80 calls to the internal network to a server running on port 8080

screenshot 2019-01-05 at 17.00.30

Step 4 – Update the CNAME-record on your domain DNS to point to the configuration

As you now have a subdomain ( pointing to you server, you can add a CNAME record on your DNS provider link these together.

I registered our domain on and from the configuration panel, I updated the CNAME Alias entry and added www pointing to

screenshot 2019-01-05 at 17.09.43

That’s it !

All should work fine now.

Hitting should open the Blog site 🙂

I hope this helps someone in future and that they will support the efforts of the team by donating to them !

Have fun !