Build "hello" Image from Alpine

Q

How to Build my "hello" Docker image from the Alpine image? I want the container to print "Hello!" in the console.

✍: FYIcenter.com

A

If you want to build a new Docker image, you can try to build it with the Alpine image as its base as shown in this tutorial.

1. Create a "Dockerfile" file with 2 instructions:

$ mkdir hello
$ cd hello

$ vi Dockerfile

FROM alpine
ENTRYPOINT echo Hello!

2. Build a new image named as "hello" using the Dockerfile in the current directory.

$ docker build --tag hello .

Sending build context to Docker daemon  4.608kB
Step 1/2 : FROM alpine
 ---> 055936d39205
Step 2/2 : ENTRYPOINT echo Hello!
 ---> Running in 82250744f0a8
Removing intermediate container 82250744f0a8
 ---> 2b2de59a503c
Successfully built 2b2de59a503c
Successfully tagged hello:latest

3. Create a new container from the image and run it.

$ docker container run hello
Hello!

4. Check the container.

$ docker container list --latest

CONTAINER ID  IMAGE  COMMAND                 CREATED        STATUS                   
e7507beb58a6  hello  "/bin/sh -c 'echo He…"  5 seconds ago  Exited (0) 5 seconds ago 

5. Check the image.

$ docker image list hello

REPOSITORY  TAG     IMAGE ID      CREATED         SIZE
hello       latest  2b2de59a503c  10 seconds ago  5.53MB

As you can see, we have created a new Docker image, with "alpine" as the based and an updated starting command.

 

ENTRYPOINT [...] - Specify Entrypoint Executable

What Is "docker build" Command

Building Docker Image with "docker build"

⇑⇑ Docker Container Platform - Tutorials

2019-06-01, 231👍, 0💬