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flaskamazon-ec2gunicornelastic-load-balancer

Why can't I access Flask API through load balancer on AWS

I deployed a Flask app with Gunicorn on EC2 instance via port 8080. Now I want to set up a load balancer to enable SSL and link to a domain eventually. The swagger page can be accessed by http://ec2-dns:8080/api. A classic type of load balancer is created with the EC2 added. Health Check is good. But when I tried to hit the endpoints using the load balancer's dns name https://lb-dns/api, it would time out with 408.

Why is it not working with the load balancer?

Solution

  • you listener should be looked like this enter image description here

    also check the security group has the right port opening