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User data Functionality in EC2 service is important and very handy tool. This allows us to execute script right after EC2 instance creation phase. By that we can execute,install any program we want or update, upgrade operating system on that virtual machine. User data functionality will run once just after completion of the instance creation sequence.  First we need to create an EC2 instance with extra steps. Choose Amazon Linux OS so we don't have to install aws-cli tool which we will need in the next steps.    Click to advanced options and add script below also tick the metadata options as well. With new metadata service it is not possible to send request to metadata service without secret key. That is why we need to use old metadata service for the demonstration purposes. Script is at the end of the page !!! We need one more thing to do, since by default all the ports are closed state. We need to add firewall allow line to open port 80 to serve our page to the public web. Click

EC2 EC2 is a service in AWS, allows you to create and manage EC2 instances. EC2 instances are basically virtual machine, highly recommend you to read (https://www.learn-aws.com/2024/11/server-virtualization.html). So long story short, EC2 allows you create/manage EC2 instances based on your resource needs.  How EC2 instances works ? There are powerfull servers on AWS datacenters and hypervisor software used to manage those EC2 instances (virtual machines) on these servers. A lot of variying CPU,RAM,networking combination of EC2 options available. There are 3 types of IP addresses for EC2 instances: Public: You are not charged for public IP assignment Lost when instance is stopped (When you stop and start instance new public address will be assigned) Associated with private IP address  Cannot be moved between instances Private: Retained when instance is stopped (Start and stop instance same private address will be assigned) Used in association with public address Elastic: You are charge

Server Virtualization Server Virtualization is key concept of cloud. This enables a lot of opportunities and also decrease the work-load of IT engineers.  Let's suppose we have a server infrastructure, to deploy our web application on it, we must allocate resources, install operating system, required libraries/tools  etc. And do same things every time when  we transfer it to other physical server or location.  And it is major hurdle to transfer application from this server to another one. Not only that but if our server has a lot of resources than it normally use, then it would cost us a lot of money too. We want to make sure that our application portable so that it will able to work on another computer/server as well. Therefore hypervisor technology came into play. Hypervisor adds abstraction layer between server (host) and to the virtual machines (VM). Hypervisor allocates resources (CPU,RAM,Storage etc.) for virtual machines (VM). Thanks to this technology we can now run multipl