Jenkins is a CI (continuous integration) server. It can be a very handy tool for developers. In this tutorial, I will show you how to install and setup Jenkins.
Step 1: Installing Jenkins
First off, we need to add the key and source list to apt. We can do this by executing the following commands.
wget -q -O - http://pkg.jenkins-ci.org/debian/jenkins-ci.org.key | apt-key add - echo deb http://pkg.jenkins-ci.org/debian binary/ > /etc/apt/sources.list.d/jenkins.list apt-get update
Next, install Jenkins. Note that this can take quite some time.
apt-get install jenkins
Step 2: Accessing Jenkins
Time to configure Jenkins. By default, Jenkins runs on port 8080, so you can access it by visiting
http://[SERVER_IP]:8080 in your web browser.
By default, everyone has access to Jenkins. You may want to add a password so that not everyone can use it. To add a password, go to “Manage Jenkins” (left). You will see a warning; click on “Setup Security” next to it.
When asked, choose “Jenkins’s own user database” and “Matrix-based security”. Anonymous should only have “Read”. Save these settings.
Jenkins will ask you to sign up now. Choose a username, password, email address, and full name. Click “Sign up”. You’ll now be the administrator of your Jenkins server.
Step 3: Using Jenkins on port 80
If you want to be able to use a domain name with your Jenkins server, but you don’t want people to have to type “:8080” after it each time, we can set up iptables so all traffic from port 80 will be redirected to port 8080. Add the following iptables rules.
iptables -A INPUT -i eth0 -p tcp --dport 80 -j ACCEPT iptables -A INPUT -i eth0 -p tcp --dport 8080 -j ACCEPT iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8080
Make sure to save and restart iptables.
service iptables save service iptables restart
Step 3: Adding a job
In Jenkins, you can have multiple jobs; that basically means that you have multiple projects that you can build. To add a job, click “New Job” (you have to be logged in). From here, it should be pretty straight-forward; if you have a Maven project, click Maven of course!
Step 4: Using Apache and SSL for Jenkins
If you want to use Apache as a reverse proxy, that’s easy with Jenkins!
You need the following Apache modules to be installed.
a2enmod proxy a2enmod proxy_http
Now add a virtual host.
<VirtualHost *:443> ServerName jenkins.domain ServerAlias www.jenkins.domain SSLEngine On SSLCertificateFile /etc/apache2/ssl/crt/jenkins.domain.crt SSLCertificateKeyFile /etc/apache2/ssl/key/jenkins.domain.key ProxyRequests Off ProxyPass / http://localhost:8080/ ProxyPassReverse / http://localhost:8080/ ProxyPassReverse / http://jenkins.host/ <Proxy http://localhost:8080/*> Order allow,deny Allow from all </Proxy> ProxyPreserveHost on </VirtualHost>
This will allow you to use Jenkins with SSL.
Step 5: Installing plugins
There are a lot of plugins for Jenkins; they allow you to do a lot of things. To install a plugin, go to “Manage Jenkins” and then click on “Manage Plugins”. This area will allow you to install plugins.
Step 6: Increase Maven’s memory
Although this is slightly off-topic, I still thought I’d share how to increase the memory assigned to Maven. You need to edit
MAVEN_OPTS. For example:
set MAVEN_OPTS="-Xmx1024m -XX:MaxPermSize=128m"