How to provide static elastic IP to ECS Farget service (web application) to connect databases in other VPCs for outbound traffic and inbound traffic for general users as HTTP/HTTPS requests?

Question

I have a web app in ECS Farget and I need to connect databases in other VPCs as outbound traffic but due to every deployment a new IP is assigned to the Farget service. 
Is there any way to assign a static elastic IP to the ECS Farget service or CIDR block with a range of IPs that can work? 
I know some of the answers related to assigning static IP to NAT gateway and then ECS Farget service with NLB in that subnet. Those things are done but I think due to NLB it is not working maybe need to add ALB as well but is it over-engineering or I am missing something?

I read this answer [how-to-use-elastic-ip-for-aws-ecs-with-farget-without-using-network-loadbalancer](https://repost.aws/questions/QUau1y0JOKTzeT4YFA0ETGIg/how-to-use-elastic-ip-for-aws-ecs-with-farget-without-using-network-loadbalancer) but cname records cannot be used for adding as IPs.

Andrii S · Accepted Answer

In case of cross vpc access to your microservices, you can use VPC Peering or Transit gateway instead of restricting access to one public vpc. It`s a more flexible configuration. But if it`s not for you in my opinion you must use alb for ingress and the NAT Gateway for egress.

Andrii S · Answer

Hello. 
You can try use ALB instead NLB it`s it is more suitable for use together with ecs https://docs.aws.amazon.com/AmazonECS/latest/userguide/create-application-load-balancer.html

Best regards, Andrii

HS · Answer

> I read this answer how-to-use-elastic-ip-for-aws-ecs-with-farget-without-using-network-loadbalancer but cname records cannot be used for adding as IPs.

No, CNAME records cannot have a static IP as value. Instead, you need to either use CNAME record and set its value to LB's domain name, or use [A record](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/ResourceRecordTypes.html#AFormat) and set its value to the static IP or [alias](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/resource-record-sets-values-alias-common.html) if the target service supports it.

HS · Answer

> Is there any way to assign a static elastic IP to the ECS Farget service or CIDR block with a range of IPs that can work?

No, ECS currently doesn't support Elastic IP, you can only have an auto-assigned public IP. Moreover, an Elastic IP is assigned randomly and cannot be specified with CIDR range either.

> I have a web app in ECS Farget and I need to connect databases in other VPCs as outbound traffic

However, if you simply need a static IP because you need it to be within a CIDR range to have it allowed by a certain security group's inbound/outbound rules, you can simply use a inbound/outbound rule that allows a certain [source/destination security group](https://docs.aws.amazon.com/vpc/latest/userguide/security-group-rules.html#security-group-referencing) (e.g.,, the one that is attached to your ECS Service) instead of CIDR IP block.

How to provide static elastic IP to ECS Farget service (web application) to connect databases in other VPCs for outbound traffic and inbound traffic for general users as HTTP/HTTPS requests?

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