I have 3 instances as staging for the frontend, backend, and blockchain. I'd like to create an autoscaling group for both three instances separately. There will be 3 autoscaling groups.
Is there any way to handle 3 autoscaling group by using one ALB? I will increase ALB later. Initially, I'd like to handle using a single alb.
Proposed architecture diagram: Click here to see architecture diagram
Best Answer
You can’t have “classic ELB” with 3 different ASGs as backends.
You can however have ALB - Application Load Balancer - with 3 Target Groups and each Target Group can have its own Auto Scaling Group attached.
On the other hand the public facing ALB will have completely different security requirements than the internal ones. The public one will be, well, public with HTTP/S open to the world. The internal ones shouldn’t have public IP at all and should only permit traffic within the VPC. You can’t achieve that if you mix it all together.
If I were you I would look at using 3x ALB - they are cheaper than ELBs and more flexible. That will make your architecture much better.
Hope that helps :)