bendathierrycom / docker-agent

Base Docker image for Jenkins Agents

Jenkins Agent Docker image

This is a base image for Docker, which includes JDK and the Jenkins agent executable (agent.jar). This executable is an instance of the Jenkins Remoting library. JDK version depends on the image and the platform, see the Configurations section below.

❗ Warning! This image used to be published as jenkinsci/slave and jenkins/slave. These images are now deprecated, use jenkins/agent.

Changelog

See GitHub releases for versions 3.35-1 and above. There is no changelog for previous versions, see the commit history.

Jenkins remoting changelogs are available here.

Usage

This image is used as the basis for the Docker Inbound Agent image. In that image, the container is launched externally and attaches to Jenkins.

This image may instead be used to launch an agent using the Launch method of Launch agent via execution of command on the master. For example on Linux you can try

docker run -i --rm --name agent --init jenkins/agent java -jar /usr/share/jenkins/agent.jar

after setting Remote root directory to /home/jenkins/agent.

or if using Windows Containers

docker run -i --rm --name agent --init jenkins/agent:jdk11-windowsservercore-ltsc2019 java -jar C:/ProgramData/Jenkins/agent.jar

after setting Remote root directory to C:\Users\jenkins\Agent.

Agent Work Directories

Starting from Remoting 3.8 there is a support of Work directories, which provides logging by default and change the JAR Caching behavior.

Call example for Linux:

docker run -i --rm --name agent1 --init -v agent1-workdir:/home/jenkins/agent jenkins/agent java -jar /usr/share/jenkins/agent.jar -workDir /home/jenkins/agent

Call example for Windows Containers:

docker run -i --rm --name agent1 --init -v agent1-workdir:C:/Users/jenkins/Work jenkins/agent:jdk11-windowsservercore-ltsc2019 java -jar C:/ProgramData/Jenkins/agent.jar -workDir C:/Users/jenkins/Work

Configurations

The image has several supported configurations, which can be accessed via the following tags:

• Linux Images:
  • latest (jdk11, bullseye-jdk11, latest-bullseye-jdk11, latest-jdk11): Latest version with the newest remoting and Java 11 (based on debian:bullseye-${builddate})
  • alpine (alpine-jdk11, latest-alpine, latest-alpine-jdk11): Small image based on Alpine Linux (based on alpine:${version})
  • archlinux (latest-archlinux, archlinux-jdk11, latest-archlinux-jdk11): Image based on Arch Linux with JDK11 (based on archlinux:latest)
  • bullseye-jdk17 (jdk17, latest-bullseye-jdk17, latest-jdk17): JDK17 version with the newest remoting (based on debian:bullseye-${builddate})

From version 4.11.2, the alpine images are tagged using the alpine OS version as well (i.e. alpine ==> alpine3.16, alpine-jdk11 ==> alpine3.16-jdk11).

• Windows Images:
  • jdk11-nanoserver-1809: Latest version with the newest remoting with Windows Nano Server and Java 11 (based on eclipse-temurin:11.xxx-jdk-nanoserver-1809)
  • jdk11-windowsservercore-ltsc2019: Latest version with the newest remoting and Java 11 (based on eclipse-temurin:11.xxx-jdk-windowsservercore-ltsc2019)
  • jdk17-nanoserver-1809: Latest version with the newest remoting with Windows Nano Server and Java 17 (based on eclipse-temurin:17.xxx-jdk-nanoserver-1809)
  • jdk17-windowsservercore-ltsc2019: Latest version with the newest remoting and Java 17 (based on eclipse-temurin:17.xxx-jdk-windowsservercore-ltsc2019)
  • jdk11-nanoserver-ltsc2022: Latest version with the newest remoting with Windows Nano Server and Java 11 (based on eclipse-temurin:11.xxx-jdk-nanoserver-ltsc2022)
  • jdk11-windowsservercore-ltsc2022: Latest version with the newest remoting and Java 11 (based on eclipse-temurin:11.xxx-jdk-windowsservercore-ltsc2022)
  • jdk17-nanoserver-ltsc2022: Latest version with the newest remoting with Windows Nano Server and Java 17 (based on eclipse-temurin:17.xxx-jdk-nanoserver-ltsc2022)
  • jdk17-windowsservercore-ltsc2022: Latest version with the newest remoting and Java 17 (based on eclipse-temurin:17.xxx-jdk-windowsservercore-ltsc2022)

The file docker-bake.hcl defines all the configuration for Linux images and their associated tags.

There are also versioned tags in DockerHub, and they are recommended for production use. See the full list here

Timezones

Using directly the jenkins/agent image

By default, the image is using the Etc/UTC timezone. If you want to use the timezone of your machine, you can mount the /etc/localtime file from the host (as per this comment) and the /etc/timezone from the host too. In this example, the machine is using the Europe/Paris timezone.

docker run --rm --tty --interactive --entrypoint=date --volume=/etc/localtime:/etc/localtime:ro --volume=/etc/timezone:/etc/timezone:ro jenkins/agent
Fri Nov 25 18:27:22 CET 2022

You can also set the TZ environment variable to the desired timezone. TZ is a standard POSIX environment variable used by many images, see Wikipedia for a list of valid values. The next command is run on a machine using the Europe/Paris timezone a few seconds after the previous one.

docker run --rm --tty --interactive --env TZ=Asia/Shanghai --entrypoint=date jenkins/agent
Sat Nov 26 01:27:58 CST 2022 

Using the jenkins/agent image as a base image

Should you want to adapt the jenkins/agent image to your local timezone while creating your own image based on it, you could use the following command (inspired by issue #291):

FROM jenkins/agent as agent
 [...]
ENV TZ=Asia/Shanghai
 [...]
RUN ln -snf /usr/share/zoneinfo/"${TZ}" /etc/localtime && echo "${TZ}" > /etc/timezone \
    && dpkg-reconfigure -f noninteractive tzdata \
 [...]