For my case, I have a Route 53 public DNS record, let say abc.com. This abc.com has a A record pointing to an ALB which routed to an EC2 (let's name it as EC2 A).
Normally, there are requests from internet calling this abc.com which will then routed to EC2 A. But for some case, EC2 in the same VPC of EC2 A will call abc.com as well. For this case, it will still go through the external path to reach EC2 A. But as both EC2 is in the same VPC, is there any way calling abc.com can be routed internally instead of going through the external path?