Setting-up-Jenkins

General procedure to install Jenkins:

$java -version  ## Check if Java is already installed
For jenkins Java 8 is required.
Download Jenkins from www.jenkins.io/download for your platform
Install Jenkin
Launch Jenkin
It shall open in web-browser at localhost:8080 
Enter initial passowrd on the first page.
Change admin password 
Your Jenkin Dashboard is ready
Explore it !!!

############## Step-by-step installation of Jenkins on ec2 instances ################
yum update -y
wget -O /etc/yum.repos.d/jenkins.repo http://pkg.jenkins-ci.org/redhat-stable/jenkins.repo  ## Add jenkins in yum repo
rpm --import http://pkg.jenkins-ci.org/redhat-stable/jenkins-ci.org.key  ##download the key necessary for proper installation
yum install jenkins         ## install Jenkins
service jenkins start       ## Start Jenkins
chkconfig jenkins on        ## Check if Jenkins is working
cat /var/lib/jenkins/secrets/initialAdminPassword           ## Get the initial admin password gor first login
          ##use the content of file for initial admin password

Edit security group inbound rules
Add rules for:
  http at port number 80
  and "custom tcp rule" at port number 8080
open : <public ip>:8080    ## e.g 172.13.0.2:8080
We will get jenkins dashboard:
Login as admin with the above-said password.
Change password.
Create new user. ##optional


********************* Connecting it with github *********************
To trigger builds every time some code is checked-in to the git, follow below steps:
At Jenkins:
In configuration of the project at jenkins under "build trigger" section select "GitHub hook trigger for GITScm polling"
At github sever:
Open your github account --> select the project repository -- > opent setting page of the repo --> select web-hooks tab
--> add webhook --> enter in Payload URL folowing URL:   http://<Name of Jenkins server>:8080/github-webhook/  
--> select "just the push event" 


**********************Setup maven tool *******************
manage jenkins---> configure global tools --> add Java jdk--> add maven home --> add git --> IN the build step write
clean package