Session Stickiness

I have a domain which points to AWS NLB, domain has Cname entry for NLB, this internal NLB is binded to istio ingress gateway ( This NLB is not created by istio default config) istio service runs on Node Port instead of Load balancer, we have created NLB manually and binded it to istio, I have Apache httpd 2.4.x container running in AWS EKS cluster which reverse proxy (Using Proxy Module) to backend tomcat service running on cluster IP exposing http port, this service points to two tomcats 8.5.x container running in same EKS cluster. Deployed sample war which display session Id info and whether is new or existing session id to test stickiness. I am able to establish connectivity from nlb - istio gateway - istio virtual service - Apache httpd server - tomcat container but session stickiness is not working and I am stuck there. Can anyone me how I can achieve the stickiness and which all layer I have to apply it,- istio and/or Apache httpd server.

Also does Istio Support Proxy and AJP protocol ?