How to distribute HTTP traffic to multiple load balancers belongs to different EKS cluster (all in diff regions),based on Custom Header values?

Question

I have :

1. 3 AWS EKS clusters, each in diff regions (us, eu, and as). Each cluster runs the same application, but with a localized database (nearest to the deployment region).
2. Each cluster has a load balancer, to distribute the traffic to multiple ec2 instances.

Now I want to distribute the HTTP traffic based on the region provided in the 'x-user-region' (custom)header.

So if Header x-user-region == 'us' , it should be directed to 'us-loadbalancer', if Header is equal to 'eu', it should be directed to 'eu-loadbalancer', and default will go to the third load balancer.

I tried achieving this by making a new AWS Application Load Balancer, but it only works in a single VPC. I tried AWS Global Accelerator, but sadly it works with ip, and custom routing does not provide any means to put conditions on Headers values.

What could be a possible solution/approach? Any help is highly appreciated.

Answer 1

...if a user registered himself as a EU citizen, his data must be saved in EU region only, even if he travels accross the globe and access the data from US or AS region.

the apis must pass a 'x-user-region' header...

Your server can response by sending a redirection to the desired endpoint based on the given x-user-region header value. If you cannot change the server code, you can use solution like Nginx example, Traefik guide, or ALB to redirect on your behalf.