Upstream clustersUpstream clusters Cluster manager Cluster warming Service discovery Supported service discovery typesOn eventually consistent service discovery DNS ResolutionHealth checking Per cluster member health check configHealth check event loggingPassive health checkingConnection pool interactionsHTTP health checking filterActive health checking fast failureHealth check identityDegraded health Connection pooling HTTP/1.1HTTP/2HTTP/3Automatic protocol selectionNumber of connection poolsHealth checking interactions Load Balancing OverviewSupported load balancersPriority levelsDegraded endpointsLocality weighted load balancingOverprovisioning FactorPanic thresholdExcluded endpointsOriginal destinationZone aware routingLoad Balancer SubsetsSlow start mode Aggregate Cluster Linearize Priority SetExampleLoad Balancing Example Outlier detection Ejection algorithmDetection typesgRPCEjection event loggingConfiguration reference Circuit breakingUpstream network filtersLoad Reporting Service (LRS)