How many nodes can be servered by a single EC2 elastic load balancer

I'm planning a web deploy开发者_运维技巧ment that could require 50+ servers all being load balanced. RackSpace cloud only allows 25 nodes per load balancer, and you can't chain the load balancers. Amazon doesn't appear to list any such limitations.

My fall-back plan is to use HXProxy, but I'd much rather use something easier to set up.

Can anyone answer the title question, or suggest an alternative architecture? (Other than anything that involves fewer nodes :) )

On EC2 you are limited only by the instance limit on your account. The default is 20, but you can request an increase at http://aws.amazon.com/contact-us/ec2-request/. When I requested an increase, the request was granted in a couple days.

If you want to stick with Rackspace, you could create multiple load balancers and use round-robin DNS to scale the load balancers out.

If you switch to Amazon ELB and put your servers in multiple zones, the scale out is handled for you automatically.

Assuming you use at least 3 zones, Amazon will be a little more expensive than Rackspace. But if you have 50 instances, the cost of your load balancer service isn't going to be your biggest concern.

You can request a higher limit from rackspace as well. Simply express your concern to one of our support guys and they'll take care of you. We limit 25 for for the sake of being cautious and feel 25 is a fair ammount for the average use. We certainly understand there are special cases and will do all we can to make a solution that's right for you!