How can use alb which is configured with ecs as target group for nlb

Question

so currently i am using alb and ecs as target group so when i created another nlb and attached ecs as target group when ip of task got updated nlb is not able to update it target group then i find out ecs it self have one attached load-balancer in my case it was alb that's why alb was working fine in case of ip change so what i am doing i am creating nlb and attaching existing alb with it but the problem is my alb is listing on port 443 and it redirecting to ecs target group so when i attached this alb with created nlb i am seeing unsecure connection so i tried tls connection in nlb target group but then i am not seeing alb in option so what should i do and can achieve, in my case i need nlb to use as vpc-end point service which we are going to provide other account endpoint for connection.

mohijeet · Answer

actually we are already using port 443 with for second nlb for other use, do we have any other option?
currently there are two load-balancer(nlb) with same endpoint so one is running critical things on 443 so what happened when i used privatelink:443 it redirected me to that thing not to actually nlb-->alb-->ecs target so in simple terms there are one private link which have two nlb both listing on port 443 its redirecting me to other nlb and not to which i actually want to

Gary Mclean · Answer

An ECS service can have more than 1 registered load balancer against it. I think it can have up to 5.
You cant register more than 1 in the GUI to an ECS Service, but you can with the CLi

https://docs.aws.amazon.com/AmazonECS/latest/developerguide/register-multiple-targetgroups.html

Riku_Kobayashi · Answer

Hello.

To use ALB as a target for NLB, you need to configure a TCP listener.  
The NLB listener should be configured with TCP:443 and ALB as the target group.  
I think the following AWS blog will be helpful for the configuration itself.  
https://aws.amazon.com/jp/blogs/networking-and-content-delivery/application-load-balancer-type-target-group-for-network-load-balancer/

How can use alb which is configured with ecs as target group for nlb

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