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GitHub removed password authentication support from August 13, 2021 instead it recommends to use either OAuth or Personal Access Token. We will see how to connect to GitHub from Jenkins using SSH keys instead of using user name and password.
It is also a good practice to use SSH keys in Jenkins jobs instead of using user name and password.
Watch the steps in YouTube channel:
Pre-requisites:
Jenkins is up and running
Credentials plug-in installed in Jenkins
Create SSH keys in your Jenkins EC2 instance
ssh-keygen
enter four times. this will create keys in .ssh folder.
Copy and paste the public key
sudo cat ~/.ssh/id_rsa.pub
Add public Keys into your respective GitHub
Add public keys into your Repository--> settings--> Deploy keys section
Click on Add Deploy Key and enter public keys and save.
Add Private Keys in Jenkins Master
Login Jenkins. Go to Manage Jenkins. click on Credentials
Click on Jenkins
Click on Global Credentials
Click on Add Credentials
Choose SSH username with private key
Choose SSH username with private key username can be anything Click on enter directly under private key option and Click Add
Copy and paste private key(not public key) of your from Jenkins instance. command is below: sudo cat ~/.ssh/id_rsa
copy the content of whole output from above command.
Click OK to save.
Now go to any Jenkins Job, you can choose this option for checking out from GitHub. Make sure you enter SSH url not https url.
That's it. This is how you use SSH url and private keys to checkout code from bitbucket or Github without entering username/password in Jenkins.
Click here to authenticate with GitHub using Personal Access Token.
Let's say that you have created EC2 instances manually even before you started using Terraform. If you like to import your EC2 instance into Terraform management you can use import command.
Theterraform importcommand is used to import your existing resources(that were created outside Terraform) into terraform state. The command currently can only import one resource at a time. This means you can't yet point Terraform import to an entire collection of resources such as an AWS VPC and import all of it.
Watch the steps in YouTube Video:
To import a resource, create a tf file first write a resource block for it in your configuration, establishing the name by which it will be known to Terraform:
sudo vi myec2.tf
resource "aws_instance" "myinstance" {
# ...instance configuration...leave this as it is
}
terraform import can be run to attach an existing EC2 instance to this resource configuration:
pick up the instance ID of EC2 instance you want to import and execute the below command: terraform import aws_instance.myinstance i-abcd1234
The AWS Command Line Interface (CLI) is a unified tool to manage your AWS services. With just one tool to download and configure, you can control multiple AWS services from the command line and automate them through scripts.
Pre-requisites:
Before you can install or update the AWS CLI version 2 on Windows, be sure you have the following:
A 64-bit version of Windows XP or later.
Admin rights to install software
AWS CLI Installation Steps on Windows
Open command prompt on your windows machine, not Git bash.
The AWS Command Line Interface (CLI) is a unified tool to manage your AWS services. With just one tool to download and configure, you can control multiple AWS services from the command line and automate them through scripts.
Jenkins has powerful feature of master slave architecture which enables distributed builds. This article we will learn how to establish slave nodes on Ubuntu machines and integrate with Jenkins Master.
Please watch the lab in YouTube
Let us learn more about Jenkins master and slave:
Jenkins Master
Your main Jenkins server is the Master. The Master’s job is to handle:
Scheduling build jobs.
Dispatching builds to the slaves for the actual execution.
Monitor the slaves (possibly taking them online and offline as required).
Recording and presenting the build results.
A Master instance of Jenkins can also execute build jobs directly.
Jenkins Slave
A Slave is a Java executable that runs on a remote machine. Following are the characteristics of Jenkins Slaves:
It hears requests from the Jenkins Master instance.
Slaves can run on a variety of operating systems.
The job of a Slave is to do as they are told to, which involves executing build jobs dispatched by the Master.
You can configure a project to always run on a particular Slave machine, or a particular type of Slave machine, or simply let Jenkins pick the next available Slave.
Let us see how to configure slave nodes on Ubuntu EC2. If you like to learn how to setup Jenkins Master on Ubuntu EC2 instance, click here.
Jenkins Master uses SSH keys to communicate with slave. You need to create ssh keys in Jenkins master by executing below command.
2. Create jenkins user and Install Java, Maven in Slave node
3. Create SSH keys and upload public keys from master to slave node.
4. verify ssh connection from master to slave
5. Register slave node in Jenkins master
6. Run build jobs in Jenkins slave
Slave node configuration
(You need to create at least t2.small Ubuntu 22.0.4 instance for this slave) only port 22 needs to be open
Change Host Name to Slave sudo hostnamectl set-hostname Slave
Install Java
sudo apt update
sudo apt install openjdk-17-jdk -y
Install Maven sudo apt install maven -y
Create User as Jenkins
sudo useradd -m jenkins
sudo -u jenkins mkdir /home/jenkins/.ssh
Now Login to Jenkins Master
Create SSH keys by executing below command:
ssh-keygen -t rsa -m PEM
Please over write your existing keys.
Copy SSH Keys from Master to Slave Execute the below command in Jenkins master EC2. sudo cat ~/.ssh/id_rsa.pub
Copy the output of the above command:
Now Login to Slave node and execute the below command sudo -u jenkins vi /home/jenkins/.ssh/authorized_keys
This will be empty file, now copy the public keys from master into above file. Once you pasted the public keys in the above file in Slave, come out of the file by entering :wq!
Now go into master node
ssh jenkins@slave_node_ip
this is to make sure master is able to connect slave node. once you are successfully logged into slave, type exit to come out of slave.
Register slave node in Jenkins:
Now to go Jenkins Master, manage jenkins, manage nodes.
Click on new node. give name and check permanent agent. give name and no of executors as 1. enter /home/jenkins as remote directory. select launch method as Launch slaves nodes via SSH. enter Slave node ip address as Host.
click on credentials. Enter user name as jenkins. Make jenkins as lowercase as it is shown. Kind as SSH username with private key. enter private key of master node directly by executing below command:
sudo cat ~/.ssh/id_rsa (Make sure you copy the whole key including the below without missing anything) -----BEGIN RSA PRIVATE KEY----- ----- -----END RSA PRIVATE KEY-----
