By assigning Elastic IP address to your EC2 Instance, you can mask the failure of an instance or software by rapidly remapping the address to another instance in your account.
What is an Elastic IP ?
Elastic IP is a public static IPv4 address which is reachable from the Internet. Basically Elastic IP addresses are used by AWS to manage its dynamic cloud computing services. An Elastic IP address is allocated to your AWS account, and is yours until you release it.
What is problem with default Public IP ?
When you launch an EC2 instance, you receive a Public IP address by which that instance is reachable. Once you stop that instance and restart that, you get a new Public IP for the same instance’s. So, Public IP get’s changed every time for an instance after stop/start. To solve this problem, we need to attach an Elastic IP to an Instance which doesn’t change after you stop / start the instance as many times.
Create and Assign Elastic IP to your EC2 instance :
- Click Allocate new address in the Elastic IPs page.
- Then, click Allocate in the next page.
- Go to Actions , and click Associate address.
- Choose the EC2 instance you are integrating and click on Associate button.
Now your EC2 instance is ready with new Elastic IP address. This Elastic IP needs to be updated in your DNS settings to map the domain name.