Jenkins slave ready to run Docker image (Jenkins Swarm Plugin)

Docker images for Jenkins slave based on Jenkins Swarm Plugin.

Works best in combination with eeacms/jenkins-master

This image is generic, thus you can obviously re-use it within your non-related EEA projects.

Supported tags and respective Dockerfile links

• :latest (Dockerfile)
• :3.47 (Dockerfile)

See older versions

Changes

• CHANGELOG.md

Base docker image

• hub.docker.com

Source code

• github.com

Installation

1. Install Docker.
2. Install Docker Compose.

Usage

$ docker run eeacms/jenkins-slave

Advanced usage

Add user and password to connect jenkins slaves to jenkins master

$ docker run eeacms/jenkins-slave -username foo -password secret

or via environment variables:

$ docker run -e JENKINS_USER=foo -e JENKINS_PASS=secret eeacms/jenkins-slave

See --help for more options:

$ docker run --rm eeacms/jenkins-slave --help

Also see EEA Jenkins master-slave orchestration for a complete guide on running a Jenkins master-slave stack.

Supported environment variables

• JENKINS_USER jenkins user to be used to connect slaves to Jenkins master. Make sure that this user has the proper rights to connect slaves and run jenkins jobs.
• JENKINS_PASS jenkins user password
• JENKINS_PASS_ENV jenkins user password; use this option if your password contains illegal characters
• JAVA_OPTS You might need to customize the JVM running Jenkins slave, typically to pass system properties or tweak heap memory settings. Use JAVA_OPTS environment variable for this purpose.
• JENKINS_NAME Name of the slave
• JENKINS_DESCRIPTION Description to be put on the slave
• JENKINS_EXECUTORS Number of executors. Default is equal with the number of available CPUs
• JENKINS_LABELS Whitespace-separated list of labels to be assigned for this slave. Multiple options are allowed.
• JENKINS_RETRY Number of retries before giving up. Unlimited if not specified.
• JENKINS_MODE The mode controlling how Jenkins allocates jobs to slaves. Can be either 'normal' (utilize this slave as much as possible) or 'exclusive' (leave this machine for tied jobs only). Default is normal.
• JENKINS_MASTER The complete target Jenkins URL like 'http://jenkins-server'. If this option is specified, auto-discovery will be skipped
• JENKINS_TUNNEL Connect to the specified host and port, instead of connecting directly to Jenkins. Useful when connection to Hudson needs to be tunneled. Can be also HOST: or :PORT, in which case the missing portion will be auto-configured like the default behavior
• JENKINS_TOOL_LOCATIONS Whitespace-separated list of tool locations to be defined on this slave. A tool location is specified as 'toolName:location'
• JENKINS_NO_RETRY_AFTER_CONNECTED Do not retry if a successful connection gets closed.
• JENKINS_AUTO_DISCOVERY_ADDRESS Use this address for udp-based auto-discovery (default 255.255.255.255)
• JENKINS_DISABLE_SSL_VERIFICATION Disables SSL verification in the HttpClient.
• JENKINS_OPTS You can provide multiple parameters via this environment like: -e JENKINS_OPTS="-labels code-analysis -mode exclusive"

Extend

Even if this image has some common system libraries pre-installed at some point your projects may have system dependencies that are not installed on this image. Thus, you'll have to build your own custom Jenkins slave Docker image based on this one by adding a Dockerfile and then run:

$ docker build -t jenkins-slave-custom .

Dockerfile

FROM eeacms/jenkins-slave

USER root
RUN apt-get update \
 && apt-get install -y --no-install-recommends \
    foo \
    bar \
 && rm -rf /var/lib/apt/lists/*
USER jenkins

Troubleshooting

If the jenkins slaves fail to connect you can either directly provide JENKINS_MASTER env URL or within your favorite browser head to http://<your.jenkins.master.ip>/configure and update Jenkins URL property to match your jenkins server IP/DOMAIN (http://<your.jenkins.master.ip>/) then restart jenkins slave.

Copyright and license

The Initial Owner of the Original Code is European Environment Agency (EEA). All Rights Reserved.

The Original Code is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Funding

European Environment Agency (EU)