EC2 Essentials:
- Amazon EC2 provides scalable virtual server in the cloud.
- An EC2 virtual server is known as "instance" and can be made up of different instance types and sizes.
- The virtual servers can run different operating systems, but most commonly run a flavor of Linux or Windows.
Instance Configuration:
- EC2 instances are designed to mimic traditional on-premise servers, but with the ability to be commissioned and decommissioned on-demand for easy scalability and elasticity.
- EC2 instances are primarily comprised of the following components:
- Amazon Machine Image (AMI): The operating system (and other settings).
- Instance Type: The hardware (compute power, ram, network bandwidth, etc.).
- Network Interface (public, private, or elastic IP addresses).
- Storage: The instances hard drive (including two options).
- Elastic Block Store (EBS) - which is "network persistent storage".
- Instance Store - "which is ephemeral storage".
Other Important EC2 Facts:
- A security group MUST be assigned to an instance during the creation process.
- Each instance MUST be placed into an existing VPC, availability zone and subnet.
- Automated (bootstrapping) custom launch commands can be passed into the instance during launch via "user-data" scripts.
- "Tag" can be used to help name and organize provisioned instances.
- Encrypted key-pairs are used to manage login authentication.
- There are limits on the amount of instances you can have running in a region at any particular time.