Now we are ready to update our Jenkins configuration to support our Dockerized build agents. The first configuration change we are going to make is to turn off the default build agents. To do this, log into your Jenkins server, and click the Manage Jenkins menu link. This will take you to a variety of configuration groups you can manage, such as system, plugins, and CLI settings. For now, we will need to go to the Configure System management group:

Once you are in the Configure System management group, you are going to change the value for # of executors to 0. It should look something like the following:

When you have changed the # of executors value to 0, you can go ahead and save the settings by clicking the Save button in the lower-left part of the screen. At this point, with this change in place, your Jenkins server will not be able to run any jobs because there are no Jenkins agents configured to run them. So let's move on quickly to the next step, which is to install the Docker plugin.