EC2 - Sizing & configurations

• Operating System (OS): Linux, Windows or Mac OS

• How much compute power & cores (CPU)

• How much random-access memory (RAM)

• How much storage space:

  • Network-attached (EBS & EFS)

  • hardware (EC2 Instance Store)

• Network card: speed of the card, Public IP address

• Firewall rules: security group

• Bootstrap script (configure at first launch): EC2 User Data

Sizing

You can use different types of EC2 instances that are optimised for different use cases (https://aws.amazon.com/ec2/instance-types/)

m5.2xlarge

• m: instance class

• 5: generation (AWS improves them over time)

• 2xlarge: size within the instance class

EC2 Instance Types

General Purpose

Great for a diversity of workloads such as web servers or code repositories

Balance between:

• Compute

• Memory

• Networking

Compute Optimized

Memory Optimized

Storage Optimized

Some T2 type examples

Instance	vCPU*	CPU Credits / hour	Mem (GiB)	Storage	Network Performance
t2.nano	1	3	0.5	EBS-Only	Low
t2.micro	1	6	1	EBS-Only	Low to Moderate
t2.small	1	12	2	EBS-Only	Low to Moderate
t2.medium	2	24	4	EBS-Only	Low to Moderate
t2.large	2	36	8	EBS-Only	Low to Moderate
t2.xlarge	4	54	16	EBS-Only	Moderate
t2.2xlarge	8	81	32	EBS-Only	Moderate

EC2 User Data

• It is possible to bootstrap our instances using an EC2 User data script.

• bootstrapping means launching commands when a machine starts.

• That script is only run once at the instance first start.

• EC2 user data is used to automate boot tasks such as:

  • Installing updates

  • Installing software

  • Downloading common files from the internet

  • Anything you can think of

• The EC2 User Data Script runs with the root user.