In simple terms working with the Cloud is nothing more but accessing different resources through the internet. Examples of resources are Ec2, servers, storage, switches, auto-scaling etc.
Server: A server is not just a physical computer, it can take the role a computer has. Any ordinary desktop can be set up as a server.
It can act as a file server. The computer will have files in a shared location and other computers can connect to this system and access those files.
For example, say you want to book a train ticket.
We have to log in to the website, the site will hit the transaction server (example spring boot server), and the transaction server will hit the mail or message server. The payment is completed and we will receive mail or message about the ticket.
The three servers are providing services without any interruption. If one among them failed to provide their service we won’t be able to book a ticket.
A server is a service to other computers and applications:
• In AWS we call the server an instance.
• In Azure we call it a virtual machine.
• In GCP we call it a virtual machine instance.
• In IBM or Alibaba, we call it a virtual machine server.
Ec2 is a component of computing. The instance is region-specific.
Region: In AWS, the region is nothing but the geographical area where you have data centers.
A Data center has resources like servers, storage, switches etc. Through the internet, you will access resources available in the data centers.
We call data centers as Availability zones or subnets in AWS. Minimum 2 datacenters are required to be in a specific region. The distance between the two data centers should be 60 km.
Bootstrapping is nothing but server creation. There are seven steps involved in instance creation.
Choose Ami (Amazon Machine image)
Image: Image is nothing but an ISO image or a bootable configuration file. Types of amazon machine types: there are 4 types.
I. Quick start. (Free tire AMIS) 2. My AMIs. (Created by us)
iii. AWS marketplace.
iv. Community AMIs.
Choose Instance type.
Configure Instance.
Add storage.
Add tags.
Configure security group.
Review
Currently, we have 1064 Linux flavors some of which are Centos, Red hat, Ubuntu Amazon Linux etc.
Linux used to be an open-source so different companies adopted Linux and developed their own flavors.
Kernel is a main component in Linux operating system. It is the core interface between a computer's hardware and its processes. It communicates between facility interactions between hardware and software components and manages resources as efficiently as possible.
It has complete control over everything in the system. It is the "portion of the operating system code that is always resident in memory.” Amazon Linux is AWS's own flavor of a Linux operating system.
The Amazon Linux AMI is a supported and maintained Linux image provided by Amazon Web Services for use on Amazon Elastic Compute Cloud (Amazon EC2).
To launch an instance we need to select Amazon's Elastic Compute Cloud(EC2) on the computer.
It provides a way for us to run “servers” on the cloud. It provides a highly scalable computing capacity, with options to choose from among the different types of operating systems. It also has components like networking, firewalls, load balancers, storage, etc.
Step 2: Select an Instance-type based on our Application Size
Step 3: Give instance details like VPC, subnet, and Auto-assign Public IP. If you don’t have any keep everything as default.
Step 6: Give security group name, necessary port numbers.