package consul import ( "context" "fmt" "github.com/armon/go-metrics" "github.com/armon/go-metrics/prometheus" "github.com/hashicorp/consul/agent/metadata" "github.com/hashicorp/consul/types" "github.com/hashicorp/raft" autopilot "github.com/hashicorp/raft-autopilot" "github.com/hashicorp/serf/serf" ) var AutopilotGauges = []prometheus.GaugeDefinition{ { Name: []string{"autopilot", "failure_tolerance"}, Help: "Tracks the number of voting servers that the cluster can lose while continuing to function.", }, { Name: []string{"autopilot", "healthy"}, Help: "Tracks the overall health of the local server cluster. 1 if all servers are healthy, 0 if one or more are unhealthy.", }, } // AutopilotDelegate is a Consul delegate for autopilot operations. type AutopilotDelegate struct { server *Server } func (d *AutopilotDelegate) AutopilotConfig() *autopilot.Config { return d.server.getOrCreateAutopilotConfig().ToAutopilotLibraryConfig() } func (d *AutopilotDelegate) KnownServers() map[raft.ServerID]*autopilot.Server { return d.server.autopilotServers() } func (d *AutopilotDelegate) FetchServerStats(ctx context.Context, servers map[raft.ServerID]*autopilot.Server) map[raft.ServerID]*autopilot.ServerStats { return d.server.statsFetcher.Fetch(ctx, servers) } func (d *AutopilotDelegate) NotifyState(state *autopilot.State) { // emit metrics if we are the leader regarding overall healthiness and the failure tolerance if d.server.raft.State() == raft.Leader { metrics.SetGauge([]string{"autopilot", "failure_tolerance"}, float32(state.FailureTolerance)) if state.Healthy { metrics.SetGauge([]string{"autopilot", "healthy"}, 1) } else { metrics.SetGauge([]string{"autopilot", "healthy"}, 0) } } } func (d *AutopilotDelegate) RemoveFailedServer(srv *autopilot.Server) { go func() { if err := d.server.RemoveFailedNode(srv.Name, false); err != nil { d.server.logger.Error("failedto remove server", "name", srv.Name, "id", srv.ID, "error", err) } }() } func (s *Server) initAutopilot(config *Config) { apDelegate := &AutopilotDelegate{s} s.autopilot = autopilot.New( s.raft, apDelegate, autopilot.WithLogger(s.logger), autopilot.WithReconcileInterval(config.AutopilotInterval), autopilot.WithUpdateInterval(config.ServerHealthInterval), autopilot.WithPromoter(s.autopilotPromoter()), ) } func (s *Server) autopilotServers() map[raft.ServerID]*autopilot.Server { servers := make(map[raft.ServerID]*autopilot.Server) for _, member := range s.serfLAN.Members() { srv, err := s.autopilotServer(member) if err != nil { s.logger.Warn("Error parsing server info", "name", member.Name, "error", err) continue } else if srv == nil { // this member was a client continue } servers[srv.ID] = srv } return servers } func (s *Server) autopilotServer(m serf.Member) (*autopilot.Server, error) { ok, srv := metadata.IsConsulServer(m) if !ok { return nil, nil } return s.autopilotServerFromMetadata(srv) } func (s *Server) autopilotServerFromMetadata(srv *metadata.Server) (*autopilot.Server, error) { server := &autopilot.Server{ Name: srv.ShortName, ID: raft.ServerID(srv.ID), Address: raft.ServerAddress(srv.Addr.String()), Version: srv.Build.String(), RaftVersion: srv.RaftVersion, Ext: s.autopilotServerExt(srv), } switch srv.Status { case serf.StatusLeft: server.NodeStatus = autopilot.NodeLeft case serf.StatusAlive, serf.StatusLeaving: // we want to treat leaving as alive to prevent autopilot from // prematurely removing the node. server.NodeStatus = autopilot.NodeAlive case serf.StatusFailed: server.NodeStatus = autopilot.NodeFailed default: server.NodeStatus = autopilot.NodeUnknown } // populate the node meta if there is any. When a node first joins or if // there are ACL issues then this could be empty if the server has not // yet been able to register itself in the catalog _, node, err := s.fsm.State().GetNodeID(types.NodeID(srv.ID)) if err != nil { return nil, fmt.Errorf("error retrieving node from state store: %w", err) } if node != nil { server.Meta = node.Meta } return server, nil }