[SOLVED] Docker: How to use bash with an Alpine based docker image?

Issue

I created a docker image from openjdk:8-jdk-alpine but when I try to execute simple commands I get the following errors:

RUN bash
/bin/sh: bash: not found

RUN ./gradlew build
env: can't execute 'bash': No such file or directory

Solution

Alpine docker image doesn't have bash installed by default. You will need to add the following commands to get bash:

RUN apk update && apk add bash

If you're using Alpine 3.3+ then you can just do:

RUN apk add --no-cache bash

To keep the docker image size small. (Thanks to comment from @sprkysnrky)

If you just want to connect to the container and don't need bash, you can use:

docker run --rm -i -t alpine /bin/sh --login

Answered By - anubhava

Answer Checked By - David Marino (WPSolving Volunteer)