AWS provides us with the option of provisioning a static IPv4 address we can attach (or detach) from our EC2 instances. This makes it easier to access our instances directly via SSH. We can also create DNS records to point at these IPs, which makes things easier.
We'll be adding two EIPs into the network: one for each EC2 instance.
graph LR A[EIP] --> B[Server A] C[DNS A Record] --> A D[TCP/22] --> C
Using DNS allows us to reference a static, unchanging DNS record throughout external systems, like Ansible, without having to worry about changing the unlaying IP addresses/records.