diff --git a/internal/cli/cli.go b/internal/cli/cli.go
index 0374a48e..a2819014 100644
--- a/internal/cli/cli.go
+++ b/internal/cli/cli.go
@@ -231,8 +231,8 @@ func (cli *CLI) AddMachine(ctx context.Context, remoteMachine RemoteMachine, clu
 	}
 	otherMachines := make([]*pb.MachineInfo, 0, len(listResp.Machines)-1)
 	for _, m := range listResp.Machines {
-		if m.Id != addResp.Machine.Id {
-			otherMachines = append(otherMachines, m)
+		if m.Machine.Id != addResp.Machine.Id {
+			otherMachines = append(otherMachines, m.Machine)
 		}
 	}
 
@@ -341,11 +341,12 @@ func (cli *CLI) ListMachines(ctx context.Context, clusterName string) error {
 	// Print the list of machines in a table format.
 	tw := tabwriter.NewWriter(os.Stdout, 0, 0, 3, ' ', 0)
 	// Print header.
-	if _, err = fmt.Fprintln(tw, "NAME\tADDRESS\tPUBLIC KEY\tENDPOINTS"); err != nil {
+	if _, err = fmt.Fprintln(tw, "NAME\tSTATE\tADDRESS\tPUBLIC KEY\tENDPOINTS"); err != nil {
 		return fmt.Errorf("write header: %w", err)
 	}
 	// Print rows.
-	for _, m := range listResp.Machines {
+	for _, member := range listResp.Machines {
+		m := member.Machine
 		subnet, _ := m.Network.Subnet.ToPrefix()
 		subnet = netip.PrefixFrom(network.MachineIP(subnet), subnet.Bits())
 		endpoints := make([]string, len(m.Network.Endpoints))
@@ -355,10 +356,18 @@ func (cli *CLI) ListMachines(ctx context.Context, clusterName string) error {
 		}
 		publicKey := secret.Secret(m.Network.PublicKey)
 		if _, err = fmt.Fprintf(
-			tw, "%s\t%s\t%s\t%s\n", m.Name, subnet, publicKey, strings.Join(endpoints, ", "),
+			tw, "%s\t%s\t%s\t%s\t%s\n", m.Name, capitalise(member.State.String()), subnet, publicKey, strings.Join(endpoints, ", "),
 		); err != nil {
 			return fmt.Errorf("write row: %w", err)
 		}
 	}
 	return tw.Flush()
 }
+
+// capitalise returns a string where the first character is upper case, and the rest is lower case.
+func capitalise(s string) string {
+	if s == "" {
+		return ""
+	}
+	return strings.ToUpper(s[:1]) + strings.ToLower(s[1:])
+}
diff --git a/internal/cli/service.go b/internal/cli/service.go
index 6d87d613..4dfb6b00 100644
--- a/internal/cli/service.go
+++ b/internal/cli/service.go
@@ -25,17 +25,17 @@ func (cli *CLI) RunService(ctx context.Context, clusterName string, opts *Servic
 		_ = c.Close()
 	}()
 
-	machResp, err := c.ListMachines(ctx, &emptypb.Empty{})
+	listResp, err := c.ListMachines(ctx, &emptypb.Empty{})
 	if err != nil {
 		return fmt.Errorf("list machines: %w", err)
 	}
 	// TODO: update ListMachine endpoint to return machine status based on the Corrosion member list.
 
-	machineIP, _ := machResp.Machines[0].Network.ManagementIp.ToAddr()
+	machineIP, _ := listResp.Machines[0].Machine.Network.ManagementIp.ToAddr()
 	if opts.Machine != "" {
-		for _, m := range machResp.Machines {
-			if m.Name == opts.Machine || m.Id == opts.Machine {
-				machineIP, _ = m.Network.ManagementIp.ToAddr()
+		for _, m := range listResp.Machines {
+			if m.Machine.Name == opts.Machine || m.Machine.Id == opts.Machine {
+				machineIP, _ = m.Machine.Network.ManagementIp.ToAddr()
 				break
 			}
 		}
diff --git a/internal/machine/api/pb/cluster.pb.go b/internal/machine/api/pb/cluster.pb.go
index 4fd1352e..94f4feb6 100644
--- a/internal/machine/api/pb/cluster.pb.go
+++ b/internal/machine/api/pb/cluster.pb.go
@@ -21,6 +21,63 @@ const (
 	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
 )
 
+type MachineMember_MembershipState int32
+
+const (
+	MachineMember_UNKNOWN MachineMember_MembershipState = 0
+	// The member is active.
+	MachineMember_UP MachineMember_MembershipState = 1
+	// The member is active, but at least one cluster member suspects its down. For all purposes,
+	// a SUSPECT member is treated as if it were UP until either it refutes the suspicion (becoming UP)
+	// or fails to do so (being declared DOWN).
+	MachineMember_SUSPECT MachineMember_MembershipState = 2
+	// The member is confirmed DOWN.
+	MachineMember_DOWN MachineMember_MembershipState = 3
+)
+
+// Enum value maps for MachineMember_MembershipState.
+var (
+	MachineMember_MembershipState_name = map[int32]string{
+		0: "UNKNOWN",
+		1: "UP",
+		2: "SUSPECT",
+		3: "DOWN",
+	}
+	MachineMember_MembershipState_value = map[string]int32{
+		"UNKNOWN": 0,
+		"UP":      1,
+		"SUSPECT": 2,
+		"DOWN":    3,
+	}
+)
+
+func (x MachineMember_MembershipState) Enum() *MachineMember_MembershipState {
+	p := new(MachineMember_MembershipState)
+	*p = x
+	return p
+}
+
+func (x MachineMember_MembershipState) String() string {
+	return protoimpl.X.EnumStringOf(x.Descriptor(), protoreflect.EnumNumber(x))
+}
+
+func (MachineMember_MembershipState) Descriptor() protoreflect.EnumDescriptor {
+	return file_internal_machine_api_pb_cluster_proto_enumTypes[0].Descriptor()
+}
+
+func (MachineMember_MembershipState) Type() protoreflect.EnumType {
+	return &file_internal_machine_api_pb_cluster_proto_enumTypes[0]
+}
+
+func (x MachineMember_MembershipState) Number() protoreflect.EnumNumber {
+	return protoreflect.EnumNumber(x)
+}
+
+// Deprecated: Use MachineMember_MembershipState.Descriptor instead.
+func (MachineMember_MembershipState) EnumDescriptor() ([]byte, []int) {
+	return file_internal_machine_api_pb_cluster_proto_rawDescGZIP(), []int{2, 0}
+}
+
 type AddMachineRequest struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -123,18 +180,73 @@ func (x *AddMachineResponse) GetMachine() *MachineInfo {
 	return nil
 }
 
+type MachineMember struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Machine *MachineInfo                  `protobuf:"bytes,1,opt,name=machine,proto3" json:"machine,omitempty"`
+	State   MachineMember_MembershipState `protobuf:"varint,2,opt,name=state,proto3,enum=api.MachineMember_MembershipState" json:"state,omitempty"`
+}
+
+func (x *MachineMember) Reset() {
+	*x = MachineMember{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[2]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *MachineMember) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*MachineMember) ProtoMessage() {}
+
+func (x *MachineMember) ProtoReflect() protoreflect.Message {
+	mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[2]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use MachineMember.ProtoReflect.Descriptor instead.
+func (*MachineMember) Descriptor() ([]byte, []int) {
+	return file_internal_machine_api_pb_cluster_proto_rawDescGZIP(), []int{2}
+}
+
+func (x *MachineMember) GetMachine() *MachineInfo {
+	if x != nil {
+		return x.Machine
+	}
+	return nil
+}
+
+func (x *MachineMember) GetState() MachineMember_MembershipState {
+	if x != nil {
+		return x.State
+	}
+	return MachineMember_UNKNOWN
+}
+
 type ListMachinesResponse struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	Machines []*MachineInfo `protobuf:"bytes,1,rep,name=machines,proto3" json:"machines,omitempty"`
+	Machines []*MachineMember `protobuf:"bytes,1,rep,name=machines,proto3" json:"machines,omitempty"`
 }
 
 func (x *ListMachinesResponse) Reset() {
 	*x = ListMachinesResponse{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[2]
+		mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[3]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -147,7 +259,7 @@ func (x *ListMachinesResponse) String() string {
 func (*ListMachinesResponse) ProtoMessage() {}
 
 func (x *ListMachinesResponse) ProtoReflect() protoreflect.Message {
-	mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[2]
+	mi := &file_internal_machine_api_pb_cluster_proto_msgTypes[3]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -160,10 +272,10 @@ func (x *ListMachinesResponse) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use ListMachinesResponse.ProtoReflect.Descriptor instead.
 func (*ListMachinesResponse) Descriptor() ([]byte, []int) {
-	return file_internal_machine_api_pb_cluster_proto_rawDescGZIP(), []int{2}
+	return file_internal_machine_api_pb_cluster_proto_rawDescGZIP(), []int{3}
 }
 
-func (x *ListMachinesResponse) GetMachines() []*MachineInfo {
+func (x *ListMachinesResponse) GetMachines() []*MachineMember {
 	if x != nil {
 		return x.Machines
 	}
@@ -177,36 +289,50 @@ var file_internal_machine_api_pb_cluster_proto_rawDesc = []byte{
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+	0x1a, 0x17, 0x2e, 0x61, 0x70, 0x69, 0x2e, 0x41, 0x64, 0x64, 0x4d, 0x61, 0x63, 0x68, 0x69, 0x6e,
+	0x65, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65, 0x12, 0x41, 0x0a, 0x0c, 0x4c, 0x69, 0x73,
+	0x74, 0x4d, 0x61, 0x63, 0x68, 0x69, 0x6e, 0x65, 0x73, 0x12, 0x16, 0x2e, 0x67, 0x6f, 0x6f, 0x67,
+	0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70, 0x74,
+	0x79, 0x1a, 0x19, 0x2e, 0x61, 0x70, 0x69, 0x2e, 0x4c, 0x69, 0x73, 0x74, 0x4d, 0x61, 0x63, 0x68,
+	0x69, 0x6e, 0x65, 0x73, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65, 0x42, 0x37, 0x5a, 0x35,
+	0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x70, 0x73, 0x76, 0x69, 0x64,
+	0x65, 0x72, 0x73, 0x6b, 0x69, 0x2f, 0x75, 0x6e, 0x63, 0x6c, 0x6f, 0x75, 0x64, 0x2f, 0x69, 0x6e,
+	0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f, 0x6d, 0x61, 0x63, 0x68, 0x69, 0x6e, 0x65, 0x2f, 0x61,
+	0x70, 0x69, 0x2f, 0x70, 0x62, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -221,28 +347,33 @@ func file_internal_machine_api_pb_cluster_proto_rawDescGZIP() []byte {
 	return file_internal_machine_api_pb_cluster_proto_rawDescData
 }
 
-var file_internal_machine_api_pb_cluster_proto_msgTypes = make([]protoimpl.MessageInfo, 3)
+var file_internal_machine_api_pb_cluster_proto_enumTypes = make([]protoimpl.EnumInfo, 1)
+var file_internal_machine_api_pb_cluster_proto_msgTypes = make([]protoimpl.MessageInfo, 4)
 var file_internal_machine_api_pb_cluster_proto_goTypes = []any{
-	(*AddMachineRequest)(nil),    // 0: api.AddMachineRequest
-	(*AddMachineResponse)(nil),   // 1: api.AddMachineResponse
-	(*ListMachinesResponse)(nil), // 2: api.ListMachinesResponse
-	(*NetworkConfig)(nil),        // 3: api.NetworkConfig
-	(*MachineInfo)(nil),          // 4: api.MachineInfo
-	(*emptypb.Empty)(nil),        // 5: google.protobuf.Empty
+	(MachineMember_MembershipState)(0), // 0: api.MachineMember.MembershipState
+	(*AddMachineRequest)(nil),          // 1: api.AddMachineRequest
+	(*AddMachineResponse)(nil),         // 2: api.AddMachineResponse
+	(*MachineMember)(nil),              // 3: api.MachineMember
+	(*ListMachinesResponse)(nil),       // 4: api.ListMachinesResponse
+	(*NetworkConfig)(nil),              // 5: api.NetworkConfig
+	(*MachineInfo)(nil),                // 6: api.MachineInfo
+	(*emptypb.Empty)(nil),              // 7: google.protobuf.Empty
 }
 var file_internal_machine_api_pb_cluster_proto_depIdxs = []int32{
-	3, // 0: api.AddMachineRequest.network:type_name -> api.NetworkConfig
-	4, // 1: api.AddMachineResponse.machine:type_name -> api.MachineInfo
-	4, // 2: api.ListMachinesResponse.machines:type_name -> api.MachineInfo
-	0, // 3: api.Cluster.AddMachine:input_type -> api.AddMachineRequest
-	5, // 4: api.Cluster.ListMachines:input_type -> google.protobuf.Empty
-	1, // 5: api.Cluster.AddMachine:output_type -> api.AddMachineResponse
-	2, // 6: api.Cluster.ListMachines:output_type -> api.ListMachinesResponse
-	5, // [5:7] is the sub-list for method output_type
-	3, // [3:5] is the sub-list for method input_type
-	3, // [3:3] is the sub-list for extension type_name
-	3, // [3:3] is the sub-list for extension extendee
-	0, // [0:3] is the sub-list for field type_name
+	5, // 0: api.AddMachineRequest.network:type_name -> api.NetworkConfig
+	6, // 1: api.AddMachineResponse.machine:type_name -> api.MachineInfo
+	6, // 2: api.MachineMember.machine:type_name -> api.MachineInfo
+	0, // 3: api.MachineMember.state:type_name -> api.MachineMember.MembershipState
+	3, // 4: api.ListMachinesResponse.machines:type_name -> api.MachineMember
+	1, // 5: api.Cluster.AddMachine:input_type -> api.AddMachineRequest
+	7, // 6: api.Cluster.ListMachines:input_type -> google.protobuf.Empty
+	2, // 7: api.Cluster.AddMachine:output_type -> api.AddMachineResponse
+	4, // 8: api.Cluster.ListMachines:output_type -> api.ListMachinesResponse
+	7, // [7:9] is the sub-list for method output_type
+	5, // [5:7] is the sub-list for method input_type
+	5, // [5:5] is the sub-list for extension type_name
+	5, // [5:5] is the sub-list for extension extendee
+	0, // [0:5] is the sub-list for field type_name
 }
 
 func init() { file_internal_machine_api_pb_cluster_proto_init() }
@@ -250,6 +381,7 @@ func file_internal_machine_api_pb_cluster_proto_init() {
 	if File_internal_machine_api_pb_cluster_proto != nil {
 		return
 	}
+	file_internal_machine_api_pb_common_proto_init()
 	file_internal_machine_api_pb_machine_proto_init()
 	if !protoimpl.UnsafeEnabled {
 		file_internal_machine_api_pb_cluster_proto_msgTypes[0].Exporter = func(v any, i int) any {
@@ -277,6 +409,18 @@ func file_internal_machine_api_pb_cluster_proto_init() {
 			}
 		}
 		file_internal_machine_api_pb_cluster_proto_msgTypes[2].Exporter = func(v any, i int) any {
+			switch v := v.(*MachineMember); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_internal_machine_api_pb_cluster_proto_msgTypes[3].Exporter = func(v any, i int) any {
 			switch v := v.(*ListMachinesResponse); i {
 			case 0:
 				return &v.state
@@ -294,13 +438,14 @@ func file_internal_machine_api_pb_cluster_proto_init() {
 		File: protoimpl.DescBuilder{
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_internal_machine_api_pb_cluster_proto_rawDesc,
-			NumEnums:      0,
-			NumMessages:   3,
+			NumEnums:      1,
+			NumMessages:   4,
 			NumExtensions: 0,
 			NumServices:   1,
 		},
 		GoTypes:           file_internal_machine_api_pb_cluster_proto_goTypes,
 		DependencyIndexes: file_internal_machine_api_pb_cluster_proto_depIdxs,
+		EnumInfos:         file_internal_machine_api_pb_cluster_proto_enumTypes,
 		MessageInfos:      file_internal_machine_api_pb_cluster_proto_msgTypes,
 	}.Build()
 	File_internal_machine_api_pb_cluster_proto = out.File
diff --git a/internal/machine/api/pb/cluster.proto b/internal/machine/api/pb/cluster.proto
index 811cba4d..ff84d7fc 100644
--- a/internal/machine/api/pb/cluster.proto
+++ b/internal/machine/api/pb/cluster.proto
@@ -21,6 +21,23 @@ message AddMachineResponse {
   MachineInfo machine = 1;
 }
 
+message MachineMember {
+  MachineInfo machine = 1;
+
+  enum MembershipState {
+    UNKNOWN = 0;
+    // The member is active.
+    UP = 1;
+    // The member is active, but at least one cluster member suspects its down. For all purposes,
+    // a SUSPECT member is treated as if it were UP until either it refutes the suspicion (becoming UP)
+    // or fails to do so (being declared DOWN).
+    SUSPECT = 2;
+    // The member is confirmed DOWN.
+    DOWN = 3;
+  }
+  MembershipState state = 2;
+}
+
 message ListMachinesResponse {
-  repeated MachineInfo machines = 1;
+  repeated MachineMember machines = 1;
 }
diff --git a/internal/machine/cluster/cluster.go b/internal/machine/cluster/cluster.go
index ab3c5be9..7ad4d035 100644
--- a/internal/machine/cluster/cluster.go
+++ b/internal/machine/cluster/cluster.go
@@ -11,6 +11,7 @@ import (
 	"log/slog"
 	"net/netip"
 	"time"
+	"uncloud/internal/corrosion"
 	"uncloud/internal/machine/api/pb"
 	"uncloud/internal/machine/network"
 	"uncloud/internal/machine/store"
@@ -20,11 +21,22 @@ import (
 type Cluster struct {
 	pb.UnimplementedClusterServer
 
-	store *store.Store
+	store      *store.Store
+	corroAdmin *corrosion.AdminClient
+	// machineID is the ID of the current machine that is running the cluster service.
+	machineID string
 }
 
-func NewCluster(store *store.Store) *Cluster {
-	return &Cluster{store: store}
+func NewCluster(store *store.Store, corroAdmin *corrosion.AdminClient) *Cluster {
+	return &Cluster{
+		store:      store,
+		corroAdmin: corroAdmin,
+	}
+}
+
+// UpdateMachineID updates the current machine ID that is running the cluster service.
+func (c *Cluster) UpdateMachineID(mid string) {
+	c.machineID = mid
 }
 
 func (c *Cluster) Init(ctx context.Context, network netip.Prefix) error {
@@ -175,6 +187,7 @@ func (c *Cluster) AddMachine(ctx context.Context, req *pb.AddMachineRequest) (*p
 	return resp, nil
 }
 
+// ListMachines lists all machines in the cluster including their membership states.
 func (c *Cluster) ListMachines(ctx context.Context, _ *emptypb.Empty) (*pb.ListMachinesResponse, error) {
 	if err := c.checkInitialised(ctx); err != nil {
 		return nil, err
@@ -184,5 +197,55 @@ func (c *Cluster) ListMachines(ctx context.Context, _ *emptypb.Empty) (*pb.ListM
 	if err != nil {
 		return nil, status.Error(codes.Internal, err.Error())
 	}
-	return &pb.ListMachinesResponse{Machines: machines}, nil
+
+	states, err := c.corroAdmin.ClusterMembershipStates(true)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "get cluster membership states: %v", err)
+	}
+
+	members := make([]*pb.MachineMember, len(machines))
+	for i, m := range machines {
+		// If the machine is not in the cluster membership states or its state is not ALIVE or SUSPECT, it is DOWN.
+		// The exception is the current machine which is always UP as it is serving this request.
+		state := pb.MachineMember_DOWN
+		addr, _ := m.Network.ManagementIp.ToAddr()
+		for _, s := range states {
+			if s.Addr.Addr().Compare(addr) == 0 &&
+				(s.State == corrosion.MembershipStateAlive || s.State == corrosion.MembershipStateSuspect) {
+				state = pb.MachineMember_UP
+				break
+			}
+		}
+		// If the machine is the current machine, it is UP.
+		if m.Id == c.machineID {
+			state = pb.MachineMember_UP
+		}
+		members[i] = &pb.MachineMember{
+			Machine: m,
+			State:   state,
+		}
+	}
+
+	return &pb.ListMachinesResponse{Machines: members}, nil
 }
+
+//func (c *Cluster) ListServices(ctx context.Context, _ *emptypb.Empty) (*pb.ListServicesResponse, error) {
+//	if err := c.checkInitialised(ctx); err != nil {
+//		return nil, err
+//	}
+//
+//	return &pb.ListServicesResponse{
+//		Messages: []*pb.Services{
+//			{
+//				Services: []*pb.Service{
+//					{
+//						Name: "service1",
+//					},
+//					{
+//						Name: "service2",
+//					},
+//				},
+//			},
+//		},
+//	}, nil
+//}
diff --git a/internal/machine/machine.go b/internal/machine/machine.go
index 9644a309..8f4a7fd4 100644
--- a/internal/machine/machine.go
+++ b/internal/machine/machine.go
@@ -256,7 +256,7 @@ func (m *Machine) Run(ctx context.Context) error {
 	// Signal that the machine is ready.
 	close(m.started)
 
-	// Control loop for managing the network controller.
+	// Control loop for managing components that depend on the machine being initialised as a cluster member.
 	errGroup.Go(
 		func() error {
 			if !m.Initialised() {
@@ -276,6 +276,9 @@ func (m *Machine) Run(ctx context.Context) error {
 				// It can be reset when leaving the cluster and then re-initialised again with a new configuration.
 				case <-m.initialised:
 					var err error
+
+					m.cluster.UpdateMachineID(m.state.ID)
+
 					// Ensure the corrosion config is up to date, including a new gossip address if the machine
 					// has just joined a cluster.
 					if err = m.configureCorrosion(); err != nil {