Docker at Windows 10 proxy propagation to containers not working

Question

I am behind cooperate proxy and running docker on windows 10. I have setup the proxy on docker as per the documentation here.

I am able to pull images but these proxy settings are not propagating to containers e.g. when I run alpine env, it does not show proxy conf. Below is my output

λ docker run alpine env                                          
  PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
  HOSTNAME=14fca5bee12f                                            
  HOME=/root                                                       

Following is the expected output as per the documentation.

On building following docker file, I get connection errors from alpine container

Docker Version

Docker version 17.12.0-ce, build c97c6d6

DockerFile

FROM alpine:latest
ADD HelloWorld.class HelloWorld.class
RUN apk --update add openjdk8-jre
ENTRYPOINT ["java", "-Djava.security.egd=file:/dev/./urandom", "HelloWorld"]

Error

Step 3/4 : RUN apk --update add openjdk8-jre                                                                      
 ---> Running in 1205b24d5044                                                                                     
fetch http://dl-cdn.alpinelinux.org/alpine/v3.7/main/x86_64/APKINDEX.tar.gz                                       
ERROR: http://dl-cdn.alpinelinux.org/alpine/v3.7/main: could not connect to server (check repositories file)      
WARNING: Ignoring APKINDEX.70c88391.tar.gz: No such file or directory                                             
fetch http://dl-cdn.alpinelinux.org/alpine/v3.7/community/x86_64/APKINDEX.tar.gz                                  
ERROR: http://dl-cdn.alpinelinux.org/alpine/v3.7/community: could not connect to server (check repositories file) 
WARNING: Ignoring APKINDEX.5022a8a2.tar.gz: No such file or directory                                             
ERROR: unsatisfiable constraints:                                                                                 
  openjdk8-jre (missing):                                                                                         
    required by: world[openjdk8-jre]                                                                              
The command '/bin/sh -c apk --update add openjdk8-jre' returned a non-zero code: 1                                

Passing Proxy as build-arg

I tried the following command and it worked. Is there any other way to automatically propagate the proxy settings as mentioned in documentation (see link above)

docker build --tag "docker-hello-world:latest" . --build-arg http_proxy=http://<username>:<password>@proxy_address:proxy_port/ --build-arg https_proxy=http://<username>:<password>@proxy_address:proxy_port/ --build-arg no_proxy=localhost,127.0.0.1

Answer 1

I had the same problem. Pulling images was working but provisioning a container was not working. In this case the solution was to provide Docker with a configuration file named ~/.docker/config.json with the following contents.

{
 "proxies":
 {
   "default":
   {
     "httpProxy": "http://proxy.server....com:8080",
     "httpsProxy": "https://proxy.server.....com:8080"
   }
 }
}

I hope this will solve your problem.