Network connectivity between two AWS EC2 instances

Introduction

This article explains the process to establish network connection (intranode communication a.k.a network communication) between two AWS EC2 instances if both belong to the same EC2 security group.

 Using private ip addresses

Login to AWS console and choose EC2 Service.

Just put the security group name itself in the “Allow” ALL TRAFFIC with source as the security group name in the common security group.

Using public ip addresses

Add two more rows like the above shown for private ip addresses, but this time with the source as the public IP (one row for each public IP address). Do not forget to end the public ip address with /32.