In my AWS account I currently have a network load balancer (TCP) pointing to two Amazon Ec2 instances over 2 Availability zones (web servers) which each have a tomcat running , this is pointed to one Ec2 instance which is the application server/database.

On the NLB, Sticky Sessions are enabled and so when I access the webservers from Chrome on a single tab everything works fine and all of my user traffic is sent to the single web server. When I open a new tab it seems that a new session is started and my user traffic can be sent to either webserver 1 or webserver 2. If it is sent to another web server, I am asked to log in again. The goal is to have all traffic for the user routed through one webserver.

Does anyone know why sticky sessions on the AWS Network Load Balancer is not working as expected? 

Pursuing Amazon training