In a company network, you operate often behind a network proxy. The network department has implemented that proxy and forces you to go through it. On your side as the administrator of the docker engine and maybe kubernetes, you need to run your network requests through that proxy.

Lukily, there is a way to go through the proxy to deploy our proxy images.

The issue you encounter

Your try to pull your docker images running the docker pull busybox command. The command tries to connect to the internet to get the images. And then you can the error :

Pulling repository busybox
2022/02/07 09:37:07 Get https://index.docker.io/v1/repositories/busybox/images: dial tcp: lookup index.docker.io on 127.0.1.1:53: no answer from server

Why are you getting that error?

Case 1: You are using boot2docker

The solution is detailed in this page.

Step 1 : clone the repository

Run the clone command and navigate inside it:

git clone https://github.com/VonC/b2d
cd b2d

Step 2: Configure the env.bat

In the b2d folder, you find the env.bat file.

Configure it to suit your needs. You can inspire from the env.bat.template.

Add your alias

At this step, you need to add your alias inside your profile file.

Save and exit the file.

Step 3: Run

Run the two .bat scripts

• Run the senv.bat
• then run the b2d.bat

Case 2: docker is installed directly on your system

If you are using version 20.10.8 or above docker moved to Go 1.16. This means that the semantics of this variable has changed. See this page for more information.

Regarding HTTP_PROXY vs. HTTPS_PROXY: for a long time, setting HTTP_PROXY alone has been good enough.

For https:// URLs, the proxy is now determined by the HTTPS_PROXY variable, with no fallback on HTTP_PROXY.

Here are the steps to configure the proxy.

Step 1: Create the dropin for systemd

In the first we are going to create a dropin for systemd. Run this command in a terminal.

mkdir /etc/systemd/system/docker.service.d

Step2: Add the variables for http and https

Then, we are going to add the infos for the proxy for the http and https protocols.

Create a file named http-proxy.conf in the dropin we have created previously

nano /etc/systemd/system/docker.service.d/http-proxy.conf

Step 3 : Configure the proxy file’s content as follows.

[Service]
Environment="HTTP_PROXY=http://myproxy.example.com:80/"
Environment="HTTPS_PROXY=http://myproxy.example.com:80/"

You can specify the endpoints that does not need a proxy. For example, if you have a local registry that you can access without a proxy.

[Service]
Environment="HTTP_PROXY=http://proxy.example.com:80/"
Environment="HTTPS_PROXY=http://proxy.example.com:80/"
Environment="NO_PROXY=localhost,127.0.0.0/8,mydocker-registry.somecorporation.com"

Step 4: Reload the configuration

To make sure that the configuration we made has been taken into account we need to go through the following steps.

1. Flush the configuration

sudo systemctl daemon-reload

2. Verify that the configuration is loaded

To do that check, run this command.

sudo systemctl show --property Environment docker

You get this output :

Environment=HTTP_PROXY=http://myproxy.example.com:80/
Environment=HTTPS_PROXY=http://myproxy.example.com:80/

3. Restart docker

Now we reboot the docker service.

sudo systemctl restart docker

Step 5: Enjoy

You are now all set.

Run the docker command again and enjoy the result.

docker pull busybox

Few links

Configure proxy on http/https from Docker