Building a docker image from scratch
This post assumes that you have a working docker environment already set up.
Here are the really simple instructions:
- create a Dockerfile
- open the Dockerfile
- add a FROM statement with a base image
- add a RUN statement for running whatever setup commands are needed
- add any additional RUN statements necessary
- add a COPY statement for copying stuff over from the local filesystem
docker build -t user/image_name:v1 .
docker run user/image_name:v1
The following is the contents of
this is a test file
As you’re writing your Dockerfile, it may be helpful to run the commands against a real image as you go, so that you can more easily predict what’s happening. Here is how to do that:
docker pull debian:latest docker run -t -i debian:latest /bin/bash
If you want to generate a docker image based off of what you did in the interactive session
vs a Dockerfile, you can take note of the image id in the console after root. E.g.
root@28934273 # specifies the user is root and the image id is 28934273. Then, you can
run whatever commands you’d like, exit the session, and run the following:
docker commit -m "ran some commands" -a "My Name" \ 28934273 user/debian:v1
- -m is the commit message
- -a is the author’s name
Now, you can run that image:
docker run -t -i user/debian:v1
You can use the image you just created as a base image in another of your Dockerfiles, so that
you can interactively set up your image initially, and then in the second step, add any
statements to actually run your software.
Documentation pulled from: