Explanation:
Go to HOME --> Azure Active Directory --> Devices --> Device settings.

Open Apple Safari and navigate to Azure Active Directory Device Registration service Over-the-Air Profile endpoint for iOS devices.
https://enterpriseregistration.windows.net/enrollmentserver/otaprofile/<yourdomainname>

Where <yourdomainname> is the domain name that you have configured with Azure Active Directory.

https://enterpriseregistration.windows.net/enrollmentserver/otaprofile/xavierdilipkumar.com

Open Apple Safari and navigate to the Device Registration Service (DRS) Over-the-Air Profile endpoint for iOS devices.
https://adf1s.contoso.com/enrollmentserver/otaprofile

1. Log on to the webpage by using a domain account credentials
2. You are prompted to install a profile. On the Install Profile screen, click Install.
3. When prompted to confirm installation of the profile, click Install Now.

4. If your device requires a PIN to unlock the device, you are prompted to enter your PIN.
5. The profile installation is finished when you see the Profile Installed screen. Click Done.
6. Return to Safari. A message informs you that you can close or leave Safari.

Goto HOME --> Azure Active Directory --> Devices --> All devices

Explanation:

Go to HOME --> Azure Active Directory --> Custom domain names --> Add custom domain --> Enter your custom domain name  --> Add domain

To use xavierdilipkumar.com with Azure AD, create a new TXT record with your domain name registrar using the info provided in the screen

Click Verify

Setup Auto SSH Login

SSH to Jenkins Master
    $ sudo -iu jenkins
Generate Public & Private RSA Key.
    $ ssh-keygen -t rsa
       public key location : /var/lib/jenkins/.ssh/id_rsa.pub
       private key location : /var/lib/jenkins/.ssh/id_rsa
Create .ssh directory on Jenkins Slave 1 from Jenkins Master
    $ ssh -i /home/ubuntu/bin/myaccountkey.pem ubuntu@3.91.65.12 mkdir -p .ssh
Attach master public key with slave authorized directory
    $ cat .ssh/id_rsa.pub | ssh -i /home/ubuntu/bin/myaccountkey.pem ubuntu@3.91.65.12 'cat >> .ssh/authorized_keys'
Verify connection
    $ ssh ubuntu@3.91.65.12
Create .ssh directory on Jenkins Slave 2 from Jenkins Master
    $ ssh -i /home/ubuntu/bin/myaccountkey.pem ubuntu@3.95.20.115 mkdir -p .ssh
Attach master public key with slave authorized directory
    $ cat .ssh/id_rsa.pub | ssh -i /home/ubuntu/bin/myaccountkey.pem ubuntu@3.95.20.115 'cat >> .ssh/authorized_keys'

Download Jenkins Slave 1 Agent Program on Jenkins Slave 1 Machine

SSH to Jenkins Slave 1
Create bin directory.
    $ mkdir ~/bin
Goto bin and download slave.jar from master
    $ cd bin 
    $ wget http://54.81.205.161:8080/jnlpJars/slave.jar

Add Jenkins Slave 1 Machine to Jenkins Master
Login to Jenkins site

Launch Command
    $ ssh ubuntu@3.91.65.12 java -jar ./bin/slave.jar

Download Jenkins Slave 2 Agent Program on Jenkins Slave 2 Machine

SSH to Jenkins Slave 2
Create bin directory.
    $ mkdir ~/bin
Goto bin and download slave.jar from master
    $ cd bin 
    $ wget http://54.81.205.161:8080/jnlpJars/slave.jar

Add Jenkins Slave 2 Machine to Jenkins Master
Login to Jenkins site

Launch Command
    $ ssh ubuntu@3.95.20.115 java -jar ./bin/slave.jar

Amazon Route 53 effectively connects user requests to infrastructure running inAWS – such as Amazon EC2 instances, Elastic Load Balancing load balancers, or Amazon S3 buckets – and can also be used to route users to infrastructure outside of AWS.

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Explanation:

A NAT (Network Address Translation) instance is, like a bastion host, an EC2 instance that lives in your public subnet. A NAT instance, however, allows your private instances outgoing connectivity to the internet while at the same time blocking inbound traffic from the internet.

A NAT (Network Address Translation) Gateways provide the same functionality as a NAT instance, however, a NAT Gateway is an AWS managed NAT service. As a result, these NAT Gateways offer greater availability and bandwidth and require less configuration and administration.

Comparison of NAT Instances and NAT Gateways

Bastion host : A bastion host is a special-purpose computer on a network specifically designed and configured to withstand attacks. The computer generally hosts a single application, for example a proxy server, and all other services are removed or limited to reduce the threat to the computer.