Amazon EC2 Concepts

From NovaOrdis Knowledge Base
Jump to navigation Jump to search

Internal

Security Concepts

AMI (Amazon Machine Image)

An Amazon machine image is a template that contains a software configuration (operating system, application server, application).

To browse through available AMIs go to the EC2 console -> Left Navigation Pane -> AMIs.

External Documentation:

Internal Documentation:

Instance

From an AMI, you can launch an instance, which is a copy of the AMI running as a virtual server on a host computer in Amazon's data center. You can launch multiple instances from an AMI. An instance can be accessed using its public DNS name or public IP address. The DNS name follows the following pattern: ec2-<public_ip>.<region_code>.compute.amazonaws.com. An instance keeps running until it is explicitly stopped or until they fail. You can start from an existing AMI, log onto the instance, customize it with additional settings and software, and then save this customized image as a new AMI.

Instance Type

Each instance type offers different compute, memory, and storage capabilities and are grouped in instance families based on these capabilities. An example of instance type is t2.micro.

External Documentation:

Instance Metadata and User Data

Subnet

AWS VPC Concepts - Subnet

Auto-Scaling

Auto-Scaling Concepts

Load Balancing

Load Balancing Concepts

Elastic IP and EC2 Instances

  • An EC2 instance cannot be reached over ssh, even if it has an Elastic IP (public) address configured on it, if the subnet has no internet gateway associated with it (no 0.0.0.0/0 route to an internet gateway)

Key Pair

Amazon EC2 Key Pairs

A key pair is region-based.

Key Pair Operations

It does. not seem to be a way to created key pairs with CloudFormation.