Hi Community,
Consider this scenario: In a single datacenter, there are several cluster nodes(or machines, not the node in upstream definition), each node deploys multiple instances as head services. All head services are functionally equivalent. Using Apisix as the gateway to access all instances. Then we have this logic structure: In this case, node1-3 can be considered as upstreams, and each upstream has N nodes(port1…N) in route configuration. We found current route configuration may sometimes be unclear and hard to manage. Consider: (1) if one instance was down, to maintain the SLA of the whole system, we may pessimistically consider all instances on the same node were down either and immediately kick-off the whole node. In this case, we can simply remove one "upstream group" in the route. (possibly done by healthcheck) (2) if one single request had failed, it is safer to make it retry with the instance on other nodes, not another instance on the same node. (without upstream group, it is a bit difficult to find the right instance to retry.) (3) if we consider node3 as a superior node (has more CPU cores or Memory, which leads to higher perf), we expect most of the traffic to be forwarded to this node. (In this case, maybe we could just adjust this upstream group’s weight) What if allow one route to support upstream list, not one upstream? What do you think? Thanks.
