Installing Jenkins

The easies way to install jenkins is following the instructions in their official page

sudo wget -O /etc/yum.repos.d/jenkins.repo http://pkg.jenkins-ci.org/redhat/jenkins.repo
sudo rpm --import http://pkg.jenkins-ci.org/redhat/jenkins-ci.org.key
sudo yum install jenkins

Jenkins require java installed, to do so check Installing java in CentOS

Configuring Jenkins

Changing the default port when Jenkins is installed as a service

The script that manages Jenkins on the system is located in /etc/init.d/jenkins

So to change the default port, 8080, the easiest way is to replace the value of the variable HTTP_PORT in the file /etc/sysconfig/jenkins. This can be done using the following command as super user, where NEW_PORT is the value of the port you want to asign

sed -i s/JENKINS_PORT=\"8080\"/JENKINS_PORT=\"{NEW_PORT}\"/g /etc/sysconfig/jenkins

Then you just need to restart the service

/etc/init.d/jenkins restart #service jenkins restart #will also works

Setting jenkins to start when the server starts

chkconfig jenkins on

Opening Jenkins ports

CentOS 7 has a new firewall application, for previous versions the service is called iptables.

firewall-cmd --permanent --zone=public --add-port={NEW_PORT}/tcp
firewall-cmd --reload