According to the AWS docs it is possible to setup HA between two EC2 instances, however I would like to use only a single EIP.
If you scroll down the page to the section related to elastic ips, the tutorial mentions that we will need 3 EIPs. I am configuring each NAT instance to reside in a different availability zone, but within the same VPC. With this config I should only need 1 EIP as the VIP, then use internal IPs to facilitate communication between NAT-1 and NAT-2 correct? Using 3 EIPs in this situation seems like overkill.
Goal is to be able to ssh to gateway.sn3.domain.com (via single EIP) and gain access even if the primary NAT (NAT-1) is down.
Looks like I may have to but an ELB in front of the NATs in order to support this.