How to setup Highly available load balancer + API gateway for Docker-swarm

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I have been thinking on how it can be possible to setup highly available load balancing + API gateway for Docker-swarm.

I have been doing research on this topic and I think I can do the following to setup a highly available layer 4 load balancing with Nginx.

have 3, 5, or 7 manager nodes, and 2 or more worker nodes. and set up Consul server, Nginx as an API gateway, and Consul-template to reload the Nginx configuration file on each Manager nodes. then set up Consul client and Registrator on Worker nodes to discover healthy services running on Worker Nodes to Consul Server running on Manager Nodes to enable Consul-template to update Nginx upstream server.

block HTTP traffic to Docker-swarm Worker nodes so that every HTTP request to Docker-swarm will hit the IPVS swarm load balancer of the Manager nodes.

direct every HTTP request to the IPVS Swarm load balancer of the Manager Nodes to the Nginx API gateway

One or more app services can be members of different or the same network group and containers on the same overlay network can communicate but if a container makes an HTTP request to container of the same or different overlay network, the request from that container should be directed to the IPVS swarm Load balancer of the Manager Nodes which will then send the request to the Nginx API gateway running on the Manager Node to reach out to the appropriate container on the worker nodes. This means that the Nginx API gateway needs to join in all the existing network groups that services of the upstream servers belongs to.

configure a direct server return when Nginx API gateway reach out to app services running on Worker Nodes

Deploy app services to run on Worker nodes and services can be scaled up and down and Worker Nodes can be scaled up and down to run more services as the user-base grows rapidly, while maintaining odd numbers for the Manager Nodes (3, 5, 7).

My question are:

What are the IPTables rule that will make IPVS swarm load balancer to send HTTP request to Nginx?

What are the IPTable rules that will block traffic coming to Worker nodes IPVS swarm load balancer so that all HTTP request goes to the IPVS swarm load balancer of the Manager Nodes?

What are the IPTable rules that will direct HTTP traffic from app services to directly hit the IPVS swarm load balancer of the Manager nodes?

What else is possible to do to make this work?