This question already has an answer here:

I am creating a site that I expect to receive DDoS attacks on occasion.

I have created two EBS AMIs on Amazon EC2. One AMI for a MySQL Database and one for the web host.

I have added an elastic IP to the web host server and have attached an A DNS record to it via Route 53 so I can access my domain.

If I were to create a load balancer, would I have to change the DNS record for the website to the load balancer's ip address? And then simply start as many instances of the web hosting ami under the load balancer as the DDoS calls for?

Is this thinking even somewhat correct?

marked as duplicate by Tom O'Connor Aug 25 '13 at 21:41

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.


A load balancer wouldn't protect you from DDoS attacks, it would just increase the amount of traffic you can handle (based on the number of backend webservers that you have at your disposal).

If you don't expect to serve a lot of traffic I wouldn't recommend setting up a load balancer just for avoiding DDoS attacks because it simply won't help that much.

Aggressive firewalling is a much better solution for this kind of problems although it's not a bullet-proof solution.

But to answer your question, if you setup a load balancer you'd need to change your DNS to point to that machine and then the load balancer would forward the traffic to your server farm.

  • "that machine" as in the load balancer? dns -> load balancer -> instances? – darkAsPitch Jun 25 '11 at 5:12
  • Yes, that's right. – fim Jun 27 '11 at 7:42

There is now active question about mitigating DDoS attacks in EC2. You may want to read it: Ec2 Denial of Service: Securing cloud based website from DOS attack

Not the answer you're looking for? Browse other questions tagged or ask your own question.