What I have learned about High Availability on AWS

This is the ninth post of content for preparing yourself for becoming an AWS Solutions Architect Associate.

In this post, we are going to focus on High Availability features within AWS.

As I have done previously let’s look at the similarities and differences to the closest equivalent in Azure. As I go through this section, I will point out some of the similar platforms.

Elastic Load Balancers (ELB)

Balances network load across virtual machines. Typically public facing.

X-forward-for header provides the IP information on where it has been forwarded to end user.

504 error is an gateway time out and application has not responded.

Load balancers are given a DNS URL and not a public IP address. This is different from Azure where Load Balancers do have Public IP addresses. In AWS, Load balancers are not free where in Azure a basic load balancer is free.

Registering a Target group in AWS is the same as creating a backend pool in Azure LB.

Auto Scaling

Three components:

Scaling Options:

Launch configuration is required before creating a scaling group.

High Availability Architecture

Cloud Formation

Elastic Beanstalk

HA with Bastion

  1. Two bastions in two AZ within public subnets behind a network load balancer.

  2. Lower cost options is to use an auto scaling group with a minimum of one for the Bastion instance using an elastic IP.

On-premises strategies

I hope that you are enjoying this information so far. It is helping me to continue to comprehend these services as I prepare for the exam myself. Thank you very much.

Reference links:

What I’ve Learned about IAM on AWS


What I’ve Learned about S3 on AWS


What I’ve Learned about EC2 on AWS


What I’ve Learned about EBS on AWS


What I’ve Learned about Cloudwatch on AWS


What I’ve Learned about RDS on AWS


What I’ve Learned about Route 53 on AWS


What I’ve Learned about VPC on AWS


What I’ve Learned about High Availability on AWS


What I’ve Learned about Applications on AWS


What I’ve Learned about Security on AWS


What I’ve Learned about Lambda and serverless on AWS