Jenkins on RHEL

The leading open source automation server, Jenkins provides hundreds of plugins 

to support building, deploying and automating any project.

Jenkins is a self-contained, open source automation server which can be used to 

automate all sorts of tasks related to building, testing, and delivering or deploying software.

Jenkins can be installed through native system packages, Docker, or even run standalone 

by any machine with a Java Runtime Environment (JRE) installed.

Jenkins is a software that allows continuous integration. Jenkins will be installed

on a server where the central build will take place. The following flowchart

demonstrates a very simple workflow of how Jenkins works.

Jenkins is an open source automation server written in Java. Jenkins helps to 

automate the non-human part of the software development process, with 

continuous integration and facilitating technical aspects of continuous delivery. 

It is a server-based system that runs in servlet containers such as Apache Tomcat.

Builds can be triggered by various means, for example by commit in a

version control system, by scheduling via a cron-like mechanism and by requesting

a specific build URL. It can also be triggered after the other builds in the queue

have completed. Jenkins functionality can be extended with plugins.

Installation of Jenkins on RHEL

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Getting the repo

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[root@dhcppc5 ~]# wget -O /etc/yum.repos.d/jenkins.repo 

 http://pkg.jenkins-ci.org/redhat/jenkins.repo

Importing Key

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[root@dhcppc5 ~]# rpm --import https://jenkins-ci.org/redhat/jenkins-ci.org.key

Install package

#################

[root@dhcppc5 ~]# yum install jenkins -y

Check the version

#########################

[root@dhcppc5 ~]# rpm -q jenkins

jenkins-2.108-1.1.noarch

Install Java

##########################

[root@dhcppc5 ~]# yum install java -y

Check the status of Firewall

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[root@dhcppc5 ~]# systemctl status firewalld

If firewalld is running either stop the firewall or add rules to the firewall

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Stop and disable firewall

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[root@dhcppc5 ~]# systemctl stop firewalld && systemctl disable firewalld

Adding rules to the firewall

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[root@dhcppc5 ~]# firewall-cmd --permanent --new-service=jenkins

success

[root@dhcppc5 ~]# firewall-cmd --permanent --add-service=jenkins

success

Reload the firewall after adding rules

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[root@dhcppc5 ~]# firewall-cmd --reload

success

Check the list of Firewall

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[root@dhcppc5 ~]# firewall-cmd --list-all

Start and enable jenkins service

############################

[root@dhcppc5 ~]# systemctl restart jenkins && systemctl enable jenkins

Check the status of jenkins service

#################################

[root@dhcppc5 ~]# systemctl status jenkins

● jenkins.service - LSB: Jenkins Automation Server

  Loaded: loaded (/etc/rc.d/init.d/jenkins; bad; vendor preset: disabled)

  Active: active (running) since Fri 2018-02-23 10:23:32 IST; 35s ago

    Docs: man:systemd-sysv-generator(8)

 Process: 25923 ExecStart=/etc/rc.d/init.d/jenkins start (code=exited, status=0/SUCCESS)

  CGroup: /system.slice/jenkins.service

          └─25948 /etc/alternatives/java -Dcom.sun.akuma.Daemon=daemonized -Djava.awt.headless=true -DJENKINS_HOME=/va...

Feb 23 10:23:27 dhcppc5 systemd[1]: Starting LSB: Jenkins Automation Server...

Feb 23 10:23:27 dhcppc5 runuser[25928]: pam_unix(runuser:session): session opened for user jenkins by (uid=0)

Feb 23 10:23:32 dhcppc5 jenkins[25923]: Starting Jenkins [  OK ]

Feb 23 10:23:32 dhcppc5 systemd[1]: Started LSB: Jenkins Automation Server.

Check the ports and service

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[root@dhcppc5 ~]# netstat -tnlp

Open localhost.localdomain:8080 in your browser, it will ask to unlock the jenkins

For unlock jenkins use password

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[root@dhcppc5 ~]# cat /var/lib/jenkins/secrets/initialAdminPassword

ac5f882f7b204564aebd53a5972dbe3e

Then click on install suggested plugins