Jenkins on MacOS HOWTO

Installation

$ brew install jenkins-lts
$ brew services start jenkins-lts

Configuration

Point your browser to http://localhost:8080 and login using password from ~/.jenkins/secrets/initialAdminPassword Create admin username/password.

Proceed with installation of the suggested plugins: iInstall s3 publisher plugin.

Next:

• Create a new pipeline;
• pick sample Hello World script;
• Build it;
• Verify success;
• examine logs.

You will get a security warning: “Building on the built-in node can be a security issue…”

Configure Jenkins Agent with Docker

I generally followed these instructions though they prooved to be insufficient:

1. Create jenkins_agent_key pair;
2. Launch the agent agent1 - note use of host port 2222 being mapped to container’s port 22:

docker run -d --rm --name=agent1 -p 2222:22 \
    -e "JENKINS_AGENT_SSH_PUBKEY=ssh-rsa AA..."\
    jenkins/ssh-agent:alpine
VARS1="HOME=|USER=|MAIL=|LC_ALL=|LS_COLORS=|LANG="
VARS2="HOSTNAME=|PWD=|TERM=|SHLVL=|LANGUAGE=|_="
VARS="${VARS1}|${VARS2}"
docker exec agent1 sh -c "env | egrep -v '^(${VARS})' >> /etc/environment"

Use MacOS Docker desktop:

• check log - it should end with a message that sshd is listening on port 22
• inspect environment variables JAVA_HOME, JAVA_VERSION, PATH - you will need the values of these in the next step.

1. Add agent1 to Jenkins as a permanent agent.

I set:

• ‘Remote root directory’ to /home/jenkins
• ‘Launch method’ picked Launch agents via SSH and then
• in Advanced section set port to 2222, add environment variables for PATH, JAVA_HOME, JAVA_VERSION with values from previous step.

Launch the agent1, confirm success.

A security message advises to set the number of executors on the Built-in node to 0. Do it.