Containerize an application

Configure the server

1. Make sure docker is installed and updated on the target machine. Run docker -v.
2. Copy Dockerfile and settings.xml to target machine.
3. Update username and password in servers context in settings.xml file.
4. Between lines 57 and 61 of the Dockerfile you can choose the target version you want to run the experiment on. Check the comments

Build the app’s container image

Run docker build --no-cache -t run-experiment .

This command used the Dockerfile to build a new container image.

The -t flag tags our image. Think of this simply as a human-readable name for the final image. Since we named the image getting-started, we can refer to that image when we run a container.

The . at the end of the docker build command tells Docker that it should look for the Dockerfile in the current directory.

Start an app container

Change the entrypoint to an interactive shell Start your container using the docker run command and specify the name of the image we just created:

Run docker run --entrypoint /bin/sh -itd run-experiment:latest

This is useful if you want to use a container like a virtual machine, and keep it running in the background when you’re not using it. If you override the entrypoint to the container with a shell, like sh or bash, and run the container with the -itd switches, Docker will run the container, detach it (run it in the background), and attach an interactive terminal. Note that this won’t run the container’s default entrypoint script, but run a shell instead. Effectively, you will have a container that stays running permanently.

Accessing Docker Containers

Once your implementation is up and running, you can access your Docker containers to get started using the app

Run the Docker list command to get a list of all Docker containers running on the system:

docker container ls

For remote access, run:

docker exec -it <container-id> /bin/bash

Running the experiment n times

Access the execution_joana project folder

cd /home/execution_joana

To run the experiment, use the following commands:

python2.7 ./script.py

To copy the files results:

docker cp f69f7e6ca1c3:/home/joana_execution/joana ./joana

Closing Docker Containers

To stop and remove a docker container, run the following command:

docker stop <container-id>