Amazon EC2 Basics

Amazon EC2 Basics

 

What is an instance type in AWS

What is an instance type in AWS

Simplified definition:
The instance type is the CPU (compute power) of your instance.

AWS Definition:
When you launch an instance, the instance type that you specify determines the hardware of the host computer used for your instance. Each instance type offers different compute, memory, and storage capabilities and are grouped in instance families based on these capabilities. Select an instance type based on the requirements of the application or software that you plan to run on your instance.

Instance types components:

1.Family:
- a way of categorizing instance types based on what they are optimized to do.

2.Type
-subcategory for each family type

3.vCPUs:
-the number of virtual CPUs the instance type uses

4.Memory (GiB):
-the amount of RAM the type uses

5.EBS optimized available:
-indicates is EBS-optimized is an option for the instance type.

6.Network performance
-network performance rating based on its data transfer rate (bandwidth capability)

What is AMI (Amazon Machine Image)

What is AMI (Amazon Machine Image)

Simplified Definition:
A pre-configured package required to launch and EC2 instance, includes an operating system, software packages and other required settings.

AWS Definition:
An Amazon Machine Image (AMI) provides the information required to launch an instance, which is a virtual server in the cloud. You specify an AMI when you launch an instance, and you can launch as many instances from the AMI as you need. You can also launch instances from as many different AMI's as you need.

Conceptuall understanding AMI's:

AMI components:

1.root volume template
-operating system
-application software
2.launch permissions
3.block device mapping
-EBS (hard drive mapping)

My Linux EC2 instance:

1.root volume template
-amazon linux
-apache web server
2.launch permissions
3.block device mapping
-EBS mapping to volume

Note:
When you create and AMI, you are essentially creating a template that you can use to launch another EC2 instance that has the exact same components as the original instance.

When you launch an EC2 instance, the first thing you do is select an AMI

AMI comes in three main categories:

1. Community AMI's
-free to use
-generally with these AMIs you are just selecting the OS you want

2.AWS marketplace AMIs:
-pay to use
-generally comes packaged with additional, licensed software

3. My AMIs
-AMIs that you create yourself

EC2 Instance Purchasing Options (Most Common)

EC2 Instance Purchasing Options (Most Common)

On-Demand
On-demand purchasing allows you to choose any instance type you like and provision/terminate it at any time (on-demand)

1. is the most expensive purchasing option
2. is the most flexible purchasing option.
3. you are only charged when the instance is running (and billed by the hour)
4. you can provision/terminate and on-demand instance at anytime.

Reserved:
Reserved purchasing allows you to purchase an instane for a set time period of one (1) or three (3) years.

1. This allow for a significant price discount over using on-demand.
2. You can select to pay upfront, partial upfront, no upfront.
3. Once you buy a reserved instance, you own it for the selected time period and are responsible for the entire price - regardless of how often you use it.

Spot:
Spot pricing is a way for you to "bid" on an instance type and only pay for and use that instance when the spot price is equal to or below your "bid" price.

What is Amazon elastic compute cloud (Amazon EC2)

What is Amazon elastic compute cloud (Amazon EC2)

Simplified definition:

Think of EC2 as your basic desktop computer

AWS Definition:

Amazon elastic compute cloud (amazon EC2) provides scalable computing capacity in the Amazon Web Services (AWS) cloud. Using Amazon EC2 eliminates your need to invest in hardware up front, so you can develop and deploy applications faster. You can use amazon EC2 to launch as many or as few virtual servers as you need, configure security,networking, and manage storage. Amazon EC2 enables you to scale up or down to handle changes in requirements or spikes in popularity, reducing your need to forecast traffic.

Conceptually understanding EC2:

Basic Computer Components:

1.Operating system (Linux or Windows)
2.Cpu (Processing Power)
3.Hard drive (Local storage)
4.Network card (Internet access)
5.Firewall (Security)
6.RAM

EC2 Instance Components:

1.AMI's (Linux or Windows)
2.Instance type (Processing power)
3.EBS (Local storage)
4.IP Addressing (Internet access)
5.Security groups (Security)
6.RAM