I have two independent applications A and B. Each application uses blue/green deployments via blue/green AWS load balancers registered in a HAProxy backend using weighted routing.
I have the requirement to route traffic across both applications (backends) based on a weight, for example routing 90% of traffic to backend A and the remaining 10% to backend B.
Is it possible to set up a frontend in HAproxy that distributes traffic across multiple backends in the above way?
I considered putting all ALBs for both applications in a single backend but it then makes independently shifting traffic between blue/green of each application more complex.
Another option is to set up internal DNS for A backend and B backend and then the default backend can route between that but ideally I would avoid going "out" of HAProxy just to route back in.