Static IP for AWS High Available Architecture

 

In a situation where the client requires IP to point their domain name in their respective DNS but the client Architecture involve Application Load balancer as the entry-point for the users.

Here the application load balancer only have public resolving DNS name which won't meet the client requirement. Hence we have two options. Our initial thought process will go to the option no 1 using an NLB in-front of the ALB. However, in Network Load Balancer also we either need to attach Elastic IP or it will provide IP's from the AWS ip pool.

The tricky part is that, the architecture needs to be highly available so we will attach the NLB to two or more availability zones. This steps will give us two or three IP's depending on the number of availability zones. Aws recommends to use the DNS endpoint here also but to meet our situation we take these IP. But in a situation like this the DNS end needs to take care of the routing of traffic to these IP by checking its availability which is not our case.

So the best solution here is provide the Global Accelerator. We can integrate the same from the Application Load Balancer itself or we can create from the Global accelerator dashboard.

This will give us two static ip with a public dns endpoint. We can use the IP to point the domain. This IP act as the entry point for the users and the GA will load the application from close region. Since here we are dealing with only one region we can skip the region routing part of GA.