Table of contents
  1. Introduction
  2. Chec proxy
  3. Check proxy
  4. Set sudo proxies
  5. Set docker proxies
  6. Set docker containers proxies

Introduction

Sometimes, we found that after using VPN, the browser can access a specific website but the software run in command line may not. In this case, we may need to configure proxies for these software.

Chec proxy

Normally, the VPN will set the environment variables about proxies for you when you open a terminal:

echo $http_proxy
echo $https_proxy

Check if these two variable are empty. If yes, then set them to you http://127.0.0.1:port-num (replace the port-num with your VPN port).

Check proxy

Check if you could fetch data from the website:

curl -I google.com

Note that you may find that curl works but ping did not. That’s because your VPN prevent ICMP traffic (which is used by ping)

Set sudo proxies

While sudo does not use the environment variables defined above by default as they are of the user, to run a sudo command using the VPN proxies:

sudo -E ...

Set docker proxies

The docker proxies could be set by modifying the /etc/docker/daemon.json to manually set the proxies:

{
    ...
    "proxies": {
      "http-proxy": "http:/127.0.0.1:prot-num",
      "https-proxy": "http:/127.0.0.1:prot-num",
      "no-proxy": "..."
    }
}

Then, restart the docker service to enable the modification in the configuration file:

sudo systemctl restart docker

Set docker containers proxies

The above section could only help you pull images using proxies from the dockerhub. But the container created by the docker does not use proxies. To make the container use proxies:

  1. If does not have an image.
    docker build --build-arg http_proxy=$http_proxy --build-arg https_proxy=$https_proxy --build-arg all_proxy=$all_proxy -t your_image_name .
  2. If an image was created.
    docker run -e http_proxy=$http_proxy -e https_proxy=$https_proxy -e all_proxy=$all_proxy -it your_image_name

    Note that according to a disccussion, you have to make sure that the VPN opens before the docker to make it works

  3. BTW You could modify the dockerfile to change the ubuntu’s apt source, e.g., using China mainland mirror source to make commands apt update and apt install run faster.