Docker environment variable settings

Docker environment variable settings

1, in Dockerfileuse, ENVthe instruction set environment variables

There are two formats:

• ENV key value
• ENV key1 = value1 key2 = value2

Example:

1、key value
    ENV PYTHON_VERSION 3.5.3
2、key=value
    ENV name1=ping name2=on_ip
3、换行
    ENV VERSION=1.0 DEBUG=on \
        NAME="Happy Feet"
4、在 Dockerfile 中使用
    $NODE_VERSION
    $PYTHON_VERSION

2, set the environment variable docker run the command

• docker run --env -e

  • Examples

    docker run -e VAR1=value1 --env VAR2=value2 ubuntu
    docker run --env VAR1=value1 --env VAR2=value2 ubuntu

  • You can also use variables that you’ve exported to your local environment:

    export VAR1=value1
    export VAR2=value2
    $ docker run --env VAR1 --env VAR2 ubuntu env | grep VAR
    VAR1=value1
    VAR2=value2

• docker run --env-file

  Use file as an environment variable, .env file as follows:

  # This is a comment
  VAR1=value1
  VAR2=value2
  USER  # which takes the value from the local environment

  Run the sample:

  docker run --env-file .env ubuntu

3, viewing environment variable

docker inspect <CONTAINER-NAME> OR <CONTAINER-ID>