Remember my tutorial on how to launch an amazon ec2  instances? I discussed there step by step procedure on how to launch an instance. Today I want to share my knowledge about Elastic IP Addresses,  these are static IP addresses designed for dynamic cloud computing. 

Basically once we launched an instance we have our local ip address and public ip address BUT TAKE NOTE ONCE YOU Reboot OR Stop your instance from the Amazon Ec2 Console you're local ip and public ip address will CHANGE, or even if you just reboot your server from the windows os your ip will change. This is really dangerous specially when you're running on a production server and you acidentally rebooted or stopped your instance without noticing it your production environment will not work!

The answer to this kind of problem is to Assign an Elastic IP Address to your instance, you can assign one elastic ip address per instance. Remember amazon has it's own regions so if you have an instance on Amazon-Singapore and  on Amazon US-West you can't assign ip addresses across regions. Each regions has it's own Elastic IP Addresses and you are only allowed 5 Elastic IP's per region.

 

Steps on how to Associate an Elastic IP Address to an EC2 Instance:

 

1. Log into your Amazon AWS Console Account (http://aws.amazon.com/)

2. You'll be redirected to your ec2 dashboard look for running instances on my case I'm running a Windows Server instance on US-West Region. Click on Elastic IP Link (see photo below)

 

 

 

 

 

 

 

 

 

 

3.  You'll be redirected to Elastic IP page wherein you can add, delete, associate, disasocciate Elastic IP Address that you own. Notice that I only have one Elastic IP address you can add more Elastic IP addresses as you wish to but, you are only limited up to 5 Elastic IP addresses per region

 

 

 

 

 

 

4. You can now associate an Elastic IP address to an instance, just right click on your Elastic IP address you'll see options there choose Associate

 

 

 

 

 

 

 

5. You'll be ask what instance would you want your elastic ip to be associated, choose one instance on your instance list

 

 

 

 

 

 

6. After assocating you'll now have an instance using Elastic IP Address, to verify log into your instance go to www.whatismyip.org the page should display your Elastic IP address