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I realize I should probably ask this question on AWS forums but I tend to get quicker responses here.

I'm trying to setup a load balanced environment in AWS. I have two EC2 instances that are mirrored and both are accessible via their own public IP address. I have the load balancer set up with the two EC2 instances added to the balancer and it's reporting that the instances are healthy.

What I'm finding is that when accessing the Load Balancer directly like the url they gave me,, page loads are ridiculously slow... like 45-70 seconds long per page load. When I access the public IP directly to one of the instances we're talking like 3-5 seconds page load.

Any ideas as to why this is so slow?

share|improve this question
Is the ELB forwarding the port traffic as you'd expect? I.e. you're passing port 80 to port 80, listening on 80 on the instances, and not doing anything complex or unexpected with the routing? – Christopher Aug 18 '12 at 13:49
I should not be slow. Amazon created a paper describing the best practices for ELB. I suggest you taking a look at it. HTH – Felipe Garcia Feb 26 '13 at 10:33
I am having the same problem, ELB works fine if there is one EC2 instance behind, after I added one more instance, sometimes the connections just hangs and resulted page failing to load – James Lin Nov 13 '13 at 20:02
Are you using an external or internal ELB? Have you tried setting up an external ELB and then putting your instances behind that ELB? In this setup your DNS will access the external ELB and your external ELB will load balance to your non-EIP EC2 instances. You can also monitor performance using CloudWatch as well as enable Access Logs on your load balancer to help troubleshoot. I have run into this issue before but the problem was on the application side not being able to work with load balancing. – VirtualJJ Oct 30 '15 at 12:49

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