Install Jenkins in Ubuntu

On Debian-based distributions, such as Ubuntu, you can install Jenkins through apt-get.
Recent versions are available in an apt repository.
You need to have a JDK and JRE installed. openjdk-6-jre and openjdk-6-jdk are suggested. As of 2011-08 gcj is known to be problematic - see https://issues.jenkins-ci.org/browse/JENKINS-743.
Please make sure to back up any current Hudson or Jenkins files you may have.

Installation

wget -q -O - http://pkg.jenkins-ci.org/debian/jenkins-ci.org.key | sudo apt-key add -
sudo sh -c 'echo deb http://pkg.jenkins-ci.org/debian binary/ > /etc/apt/sources.list.d/jenkins.list'
sudo aptitude update
sudo aptitude install jenkins

Upgrade

Once installed like this, you can update to the later version of Jenkins (when it comes out) by running the following commands:

sudo aptitude update
sudo aptitude install jenkins

(aptitude or apt-get doesn't make any difference.)

What does this package do?

• Jenkins will be launched as a daemon up on start. See /etc/init.d/jenkins for more details.
• The 'jenkins' user is created to run this service.
• Log file will be placed in /var/log/jenkins/jenkins.log. Check this file if you are troubleshooting Jenkins.
• /etc/default/jenkins will capture configuration parameters for the launch.
• By default, Jenkins listen on port 8080. Access this port with your browser to start configuration.

Setting up an Apache Proxy for port 80 -> 8080

• This configuration will setup Apache2 to proxy port 80 to 8080 so that you can keep Jenkins on 8080.
• sudo aptitude install apache2
• sudo a2enmod proxy
• sudo a2enmod proxy_http
• sudo a2enmod vhost_alias

  do not do this next command if you already have virtual hosting setup that depends on the default site. See my comment below - danapsimer

• sudo a2dissite default
• Create a file called jenkins in /etc/apache2/sites-available

<VirtualHost *:80>
 ServerAdmin webmaster@localhost
 ServerName ci.company.com
 ServerAlias ci
 ProxyRequests Off
 <Proxy *>
  Order deny,allow
  Allow from all
 </Proxy>
 ProxyPreserveHost on
 ProxyPass / http://localhost:8080/
</VirtualHost>

• sudo a2ensite jenkins
• sudo apache2ctl restart

Setting up an Nginx Proxy for port 80 -> 8080

This configuration will setup Nginx to proxy port 80 to 8080 so that you can keep Jenkins on 8080. Instructions originally found in a GitHub Gist from rdegges: https://gist.github.com/913102

• Install Nginx.

  sudo aptitude -y install nginx
  

• Remove default configuration.

  cd /etc/nginx/sites-available
  sudo rm default
  

• Create new configuration for Jenkins. This example uses cat, but you can use your favorite text editor. Make sure to replace 'ci.yourcompany.com' with your domain name.
  Note: Sometimes your permissions (umask, etc) might be setup such that this won't work. Create the file somewhere else then copy it into place if you run into that problem.

  sudo cat > jenkins
  upstream app_server {
      server 127.0.0.1:8080 fail_timeout=0;
  }
  
  server {
      listen 80;
      listen [::]:80 default ipv6only=on;
      server_name ci.yourcompany.com;
  
      location / {
          proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
          proxy_set_header Host $http_host;
          proxy_redirect off;
  
          if (!-f $request_filename) {
              proxy_pass http://app_server;
              break;
          }
      }
  }
  ^D # Hit CTRL + D to finish writing the file
  

• Link your configuration from sites-available to sites-enabled:

  sudo ln -s /etc/nginx/sites-available/jenkins /etc/nginx/sites-enabled/
  

• Restart Nginx

  sudo service nginx restart
  

Where to go from here?

• You might want to make Jenkins visible through Apache, to make it available on port 80 (for example, http://myserver/jenkins/ instead of http://myserver:8080/). See this blog for more details