In other words, by setting up a cloud environment, when Jenkins pipeline runs, it references the cloud setup and start up instances of the images as agents (slaves).

After the pipeline is done, Jenkins will stop and remove the containers running those images.

Also, by making an explicit volume, we can manage it and attach to another container for upgrades.

Go to Manage Jenkins click on Manage Plugins Go to Available Tab select Docker Plugin.

The configuration will tell the plugin which Docker Image to use for the agent and which Docker daemon to run the containers and builds on.

The plugin treats Docker as a cloud provider, spinning up containers as and when the build requires them.

There we can fill out the Docker host parameters for spinning up the slaves.

Depending on the launch method we select, theres some prerequisites for the Docker image to be used.

We can just use jenkinsssh-slave as a basis for a custom image.

A SSH key (based on unique Jenkins master instance identity) can be injected in container on startup, we dont need any credential set as long as we use standard openssl sshd.

Select Restrict where this project can be run option and select the docker host as slave using the label as shown below.

The image used was jenkinsjnlp-slave and the Dockerfile looks like this.

LABEL DescriptionThis is a base image, which allows connecting Jenkins agents via JNLP protocols VendorJenkins project Version3.27.

Docker For Mac Ssh Agent