Amazon Load balancer not working?

Question

I have an aws Elastic Load Balancer. Sometimes Elastic Load Balancer works sometimse not. Soemetimes I am able to hit the app sometimes it gives me the blank page . Why its happening so

Answer 1

You should check ping path and ping port on ELB, whether you get response. It seems that ELB brings the instances down as failed healthcheck.

Answer 2

AWS Application Load Balancers are notoriously susceptible to DDoS attacks, a simple SYN flood will bring down a load balancer, and what's worse is that you won't know that it's down, because the AWS Dashboard doesn't expose anything about the load balancer other than some basic HTTP level metrics.