How do you run `apt-get` in a dockerfile behind a

问题:

I am running a virtual machine (Ubuntu 13.10) with docker (version 0.8.1, build a1598d1). I am trying to build an image with a dockerfile. First, I want to update the packages (using the code below - the proxy is obfuscated) but apt-get times out with the error: Could not resolve 'archive.ubuntu.com'.

FROM ubuntu:13.10
ENV HTTP_PROXY <HTTP_PROXY>
ENV HTTPS_PROXY <HTTPS_PROXY>
RUN export http_proxy=$HTTP_PROXY
RUN export https_proxy=$HTTPS_PROXY
RUN apt-get update && apt-get upgrade

I have also run the following in the host system:

sudo HTTP_PROXY=http://<PROXY_DETAILS>/ docker -d &

The host is able to run apt-get without issue.

How can I change the dockerfile to allow it to reach the ubuntu servers from within the container?

Update

I ran the code in CentOS (changing the FROM ubuntu:13.10 to FROM centos) and it worked fine. It seems to be a problem with Ubuntu.

回答1:

UPDATE:

You have wrong capitalization of environment variables in ENV. Correct one is http_proxy. Your example should be:

FROM ubuntu:13.10
ENV http_proxy <HTTP_PROXY>
ENV https_proxy <HTTPS_PROXY>
RUN apt-get update && apt-get upgrade

or

FROM centos
ENV http_proxy <HTTP_PROXY>
ENV https_proxy <HTTPS_PROXY>
RUN yum update 

All variables specified in ENV are prepended to every RUN command. Every RUN command is executed in own container/environment, so it does not inherit variables from previous RUN commands!

Note: There is no need to call docker daemon with proxy for this to work, although if you want to pull images etc. you need to set the proxy for docker deamon too. You can set proxy for daemon in /etc/default/docker in Ubuntu (it does not affect containers setting).

---

Also, this can happen in case you run your proxy on host (i.e. localhost, 127.0.0.1). Localhost on host differ from localhost in container. In such case, you need to use another IP (like 172.17.42.1) to bind your proxy to or if you bind to 0.0.0.0, you can use 172.17.42.1 instead of 127.0.0.1 for connection from container during docker build.

You can also look for an example here: How to rebuild dockerfile quick by using cache?

回答2:

Updated on 02/10/2018

With new feature in docker option --config, you needn't set Proxy in Dockerfile any more. You can have same Dockerfile to be used in and out corporate environment.

--config string      Location of client config files (default "~/.docker/config.json")

or environment variable DOCKER_CONFIG

`DOCKER_CONFIG` The location of your client configuration files.

$ export DOCKER_CONFIG=~/.docker/

https://docs.docker.com/engine/reference/commandline/cli/

https://docs.docker.com/network/proxy/

I recommend to set proxy with httpProxy, httpsProxy, ftpProxy and noProxy.

{
 "proxies":
 {
   "default":
   {
     "httpProxy": "http://127.0.0.1:3001",
     "httpsProxy": "http://127.0.0.1:3001",
     "ftpProxy": "http://127.0.0.1:3001",
     "noProxy": "*.test.example.com,.example2.com"
   }
 }
}

Adjust proxy IP and port if needed and save to ~/.docker/config.json

After yo set properly with it, you can run docker build and docker run as normal.

$ docker build -t demo . 

$ docker run -ti --rm demo env|grep -ri proxy
(standard input):http_proxy=http://127.0.0.1:3001
(standard input):HTTPS_PROXY=http://127.0.0.1:3001
(standard input):https_proxy=http://127.0.0.1:3001
(standard input):NO_PROXY=*.test.example.com,.example2.com
(standard input):no_proxy=*.test.example.com,.example2.com
(standard input):FTP_PROXY=http://127.0.0.1:3001
(standard input):ftp_proxy=http://127.0.0.1:3001
(standard input):HTTP_PROXY=http://127.0.0.1:3001

Old answer

Below setting in Dockerfile works for me. I tested in CoreOS, Vagrant and boot2docker. Suppose the proxy port is 3128

In Centos:

ENV http_proxy=ip:3128 
ENV https_proxy=ip:3128

In Ubuntu:

ENV http_proxy 'http://ip:3128'
ENV https_proxy 'http://ip:3128'

Be careful of the format, some have http in it, some haven't, some with single quota. if the IP address is 192.168.0.193, then the setting will be:

In Centos:

ENV http_proxy=192.168.0.193:3128 
ENV https_proxy=192.168.0.193:3128

In Ubuntu:

ENV http_proxy 'http://192.168.0.193:3128'
ENV https_proxy 'http://192.168.0.193:3128'

If you need set proxy in coreos, for example to pull the image

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

[Service]
Environment="HTTP_PROXY=http://192.168.0.193:3128"

回答3:

You can use the --build-arg option when you want to build using a Dockerfile.

From a link on https://github.com/docker/docker/issues/14634 , see the section "Build with --build-arg with multiple HTTP_PROXY":

[root@pppdc9prda2y java]# docker build 
  --build-arg https_proxy=$HTTP_PROXY --build-arg http_proxy=$HTTP_PROXY 
  --build-arg HTTP_PROXY=$HTTP_PROXY --build-arg HTTPS_PROXY=$HTTP_PROXY 
  --build-arg NO_PROXY=$NO_PROXY  --build-arg no_proxy=$NO_PROXY -t java .

NOTE: On your own system, make sure you have set the HTTP_PROXY and NO_PROXY environment variables.

回答4:

before any apt-get command in your Dockerfile you should put this line

COPY apt.conf /etc/apt/apt.conf

Dont'f forget to create apt.conf in the same folder that you have the Dockerfile, the content of the apt.conf file should be like this:

Acquire::socks::proxy "socks://YOUR-PROXY-IP:PORT/";
Acquire::http::proxy "http://YOUR-PROXY-IP:PORT/";
Acquire::https::proxy "http://YOUR-PROXY-IP:PORT/";

if you use username and password to connect to your proxy then the apt.conf should be like as below:

Acquire::socks::proxy "socks://USERNAME:PASSWORD@YOUR-PROXY-IP:PORT/";
Acquire::http::proxy "http://USERNAME:PASSWORD@YOUR-PROXY-IP:PORT/";
Acquire::https::proxy "http://USERNAME:PASSWORD@YOUR-PROXY-IP:PORT/";

for example :

Acquire::https::proxy "http://foo:bar@127.0.0.1:8080/";

Where the foo is the username and bar is the password.

回答5:

Use --build-arg in lower case environment variable:

docker build --build-arg http_proxy=http://proxy:port/ --build-arg https_proxy=http://proxy:port/ --build-arg ftp_proxy=http://proxy:port --build-arg no_proxy=localhost,127.0.0.1,company.com -q=false .

回答6:

i had the same problem and found another little workaround: i have a provisioner script that is added form the docker build environment. In the script i set the environment variable dependent on a ping check:

Dockerfile:

ADD script.sh /tmp/script.sh
RUN /tmp/script.sh

script.sh:

if ping -c 1 ix.de ; then
    echo "direct internet doing nothing"
else
    echo "proxy environment detected setting proxy"
    export http_proxy=<proxy address>
fi

this is still somewhat crude but worked for me

回答7:

If you have the proxies set up correctly, and still cannot reach the internet, it could be the DNS resolution. Check /etc/resolve.conf on the host Ubuntu VM. If it contains nameserver 127.0.1.1, that is wrong.

Run these commands on the host Ubuntu VM to fix it:

sudo vi /etc/NetworkManager/NetworkManager.conf
# Comment out the line `dns=dnsmasq` with a `#`

# restart the network manager service
sudo systemctl restart network-manager

cat /etc/resolv.conf

Now /etc/resolv.conf should have a valid value for nameserver, which will be copied by the docker containers.

回答8:

As suggested by other answers, --build-arg may be the solution. In my case, I had to add --network=host in addition to the --build-arg options.

docker build -t <TARGET> --build-arg http_proxy=http://<IP:PORT> --build-arg https_proxy=http://<IP:PORT> --network=host .

回答9:

We are doing ...

ENV http_proxy http://9.9.9.9:9999
ENV https_proxy http://9.9.9.9:9999

and at end of dockerfile ...

ENV http_proxy ""
ENV https_proxy ""

This, for now (until docker introduces build env vars), allows the proxy env vars to be used for the build ONLY without exposing them

The alternative to solution is NOT to build your images locally behind a proxy but to let docker build your images for you using docker "automated builds". Since docker is not building the images behind your proxy the problem is solved. An example of an automated build is available at ...

https://github.com/danday74/docker-nginx-lua (GITHUB repo)

https://registry.hub.docker.com/u/danday74/nginx-lua (DOCKER repo which is watching the github repo using an automated build and doing a docker build on a push to the github master branch)

回答10:

and If you want to set proxy for wget you should put these line in your Dockerfile

ENV http_proxy YOUR-PROXY-IP:PORT/
ENV https_proxy YOUR-PROXY-IP:PORT/
ENV all_proxy YOUR-PROXY-IP:PORT/

回答11:

As Tim Potter pointed out, setting proxy in dockerfile is horrible. When building the image, you add proxy for your corporate network but you may be deploying in cloud or a DMZ where there is no need for proxy or the proxy server is different.

Also, you cannot share your image with others outside your corporate n/w.

回答12:

A slight alternative to the answer provided by @Reza Farshi (which works better in my case) is to write the proxy settings out to /etc/apt/apt.conf using echo via the Dockerfile e.g.:

FROM ubuntu:16.04

RUN echo "Acquire::http::proxy \"$HTTP_PROXY\";\nAcquire::https::proxy \"$HTTPS_PROXY\";" > /etc/apt/apt.conf

# Test that we can now retrieve packages via 'apt-get'
RUN apt-get update

The advantage of this approach is that the proxy addresses can be passed in dynamically at image build time, rather than having to copy the settings file over from the host.

e.g.

docker build --build-arg HTTP_PROXY=http://<host>:<port> --build-arg HTTPS_PROXY=http://<host>:<port> .

as per docker build docs.