Small improvements and tidying up - deferred slave port setting

Author: michaelneale

Dockerfile

@@ -3,8 +3,7 @@ FROM ubuntu:14.04
 RUN echo "1.565.2" > .lts-version-number
 
 RUN apt-get update && apt-get install -y wget git curl zip && apt-get clean
-RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk && apt-get clean
-RUN apt-get update && apt-get install -y maven ant ruby rbenv make && apt-get clean
+RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk && apt-get clean bash
 
 RUN wget -q -O - http://pkg.jenkins-ci.org/debian-stable/jenkins-ci.org.key | sudo apt-key add -
 RUN echo deb http://pkg.jenkins-ci.org/debian-stable binary/ >> /etc/apt/sources.list
@@ -18,16 +17,15 @@ RUN chmod +x /usr/local/bin/jenkins.sh
 USER jenkins
 
 # VOLUME /var/jenkins_home - bind this in via -v if you want to make this persistent.
-VOLUME /var/jenkins_home
 ENV JENKINS_HOME /var/jenkins_home
 
 # define url prefix for running jenkins behind Apache (https://wiki.jenkins-ci.org/display/JENKINS/Running+Jenkins+behind+Apache)
 ENV JENKINS_PREFIX /
 
 # for main web interface:
-EXPOSE 8080 
+EXPOSE 8080
 
 # will be used by attached slave agents:
-EXPOSE 50000 
+EXPOSE 50000
 
 CMD ["/usr/local/bin/jenkins.sh"]

README.md

@@ -1,6 +1,6 @@
 # Official Jenkins Docker image
 
-The Jenkins Continuous Integration and Delivery server. 
+The Jenkins Continuous Integration and Delivery server.
 
 This is a fully functional Jenkins server, based on the Long Term Support release
 http://jenkins-ci.org/
@@ -15,29 +15,36 @@ http://jenkins-ci.org/
 docker run -p 8080:8080 jenkins
 ```
 
-This will store the workspace in /var/jenkins_home. All Jenkins data lives in there - including plugins and configuration. You will probably want to make that a persistent volume (recommended):
+This will store the workspace in /var/jenkins_home. All Jenkins data lives in there - including plugins and configuration.
+You will probably want to make that a persistent volume (recommended):
 
 ```
-docker run --name myjenkins -p 8080:8080 -v /your/home:/var/jenkins_home jenkins
+docker run -p 8080:8080 -v /your/home:/var/jenkins_home jenkins
 ```
 
-The volume for the "myjenkins" named container will then be persistent.
+This will store the jenkins data in /your/home on the host.
+Ensure that /your/home is accessible by the jenkins user in container (jenkins user - uid 102 normally - or use -u root).
 
-You can also bind mount in a volume from the host: 
 
-First, ensure that /your/home is accessible by the jenkins user in container (jenkins user - uid 102 normally - or use -u root), then: 
+You can also use a volume container:
 
 ```
-docker run -p 8080:8080 -v /your/home:/var/jenkins_home jenkins
+docker run --name myjenkins -p 8080:8080 -v /var/jenkins_home jenkins
 ```
 
+Then myjenkins container has the volume (please do read about docker volume handling to find out more).
+
 ## Backing up data
 
-If you bind mount in a volume - you can simply back up that directory (which is jenkins_home) at any time. This is highly recommended. Treat the jenkins_home directory as you would a database - in Docker you would generally put a database on a volume.
+If you bind mount in a volume - you can simply back up that directory
+(which is jenkins_home) at any time.
+
+This is highly recommended. Treat the jenkins_home directory as you would a database - in Docker you would generally put a database on a volume.
 
-If your volume is inside a container - you can use ```docker cp $ID:/var/jenkins_home``` command to extract the data. 
+If your volume is inside a container - you can use ```docker cp $ID:/var/jenkins_home``` command to extract the data.
+Note that some symlinks on some OSes may be converted to copies (this can confuse jenkins with lastStableBuild links etc)
 
-# Attaching build executors 
+# Attaching build executors
 
 You can run builds on the master (out of the box) buf if you want to attach build slave servers: make sure you map the port: ```-p 50000:50000``` - which will be used when you connect a slave agent.
 
@@ -46,7 +53,10 @@ You can run builds on the master (out of the box) buf if you want to attach buil
 
 # Upgrading
 
-All the data needed is in the /var/jenkins_home directory - so depending on how you manage that - depends on how you upgrade. Generally - you can copy it out - and then "docker pull" the image again - and you will have the latest LTS - you can then start up with -v pointing to that data (/var/jenkins_home) and everything will be as you left it. 
+All the data needed is in the /var/jenkins_home directory - so depending on how you manage that - depends on how you upgrade. Generally - you can copy it out - and then "docker pull" the image again - and you will have the latest LTS - you can then start up with -v pointing to that data (/var/jenkins_home) and everything will be as you left it.
 
+As always - please ensure that you know how to drive docker - especially volume handling!
 
+# Questions?
 
+Jump on irc.freenode.net and the #jenkins room. Ask!

init.groovy

@@ -1,5 +1,9 @@
 import hudson.model.*;
 import jenkins.model.*;
 
-println "--> setting agent port for jnlp"
-Jenkins.instance.setSlaveAgentPort(50000)
+
+Thread.start {
+      sleep 10000
+      println "--> setting agent port for jnlp"
+      Jenkins.instance.setSlaveAgentPort(50000)
+}