Exemplo n.º 1
0
Arquivo: rpc.go Projeto: eswdd/bosun
// handleJoinRequest handles a request to join the cluster
func (r *rpc) handleJoinRequest(req *internal.JoinRequest) (*internal.JoinResponse, error) {
	r.traceCluster("join request from: %v", *req.Addr)

	node, err := func() (*NodeInfo, error) {

		// attempt to create the node
		node, err := r.store.CreateNode(*req.Addr)
		// if it exists, return the existing node
		if err == ErrNodeExists {
			node, err = r.store.NodeByHost(*req.Addr)
			if err != nil {
				return node, err
			}
			r.logger.Printf("existing node re-joined: id=%v addr=%v", node.ID, node.Host)
		} else if err != nil {
			return nil, fmt.Errorf("create node: %v", err)
		}

		peers, err := r.store.Peers()
		if err != nil {
			return nil, fmt.Errorf("list peers: %v", err)
		}

		// If we have less than 3 nodes, add them as raft peers if they are not
		// already a peer
		if len(peers) < MaxRaftNodes && !raft.PeerContained(peers, *req.Addr) {
			r.logger.Printf("adding new raft peer: nodeId=%v addr=%v", node.ID, *req.Addr)
			if err = r.store.AddPeer(*req.Addr); err != nil {
				return node, fmt.Errorf("add peer: %v", err)
			}
		}
		return node, err
	}()

	nodeID := uint64(0)
	if node != nil {
		nodeID = node.ID
	}

	if err != nil {
		return nil, err
	}

	// get the current raft peers
	peers, err := r.store.Peers()
	if err != nil {
		return nil, fmt.Errorf("list peers: %v", err)
	}

	return &internal.JoinResponse{
		Header: &internal.ResponseHeader{
			OK: proto.Bool(true),
		},
		EnableRaft: proto.Bool(raft.PeerContained(peers, *req.Addr)),
		RaftNodes:  peers,
		NodeID:     proto.Uint64(nodeID),
	}, err

}
Exemplo n.º 2
0
Arquivo: state.go Projeto: eswdd/bosun
func (r *localRaft) open() error {
	r.closing = make(chan struct{})

	s := r.store
	// Setup raft configuration.
	config := raft.DefaultConfig()
	config.LogOutput = ioutil.Discard

	if s.clusterTracingEnabled {
		config.Logger = s.Logger
	}
	config.HeartbeatTimeout = s.HeartbeatTimeout
	config.ElectionTimeout = s.ElectionTimeout
	config.LeaderLeaseTimeout = s.LeaderLeaseTimeout
	config.CommitTimeout = s.CommitTimeout

	// If no peers are set in the config or there is one and we are it, then start as a single server.
	if len(s.peers) <= 1 {
		config.EnableSingleNode = true
		// Ensure we can always become the leader
		config.DisableBootstrapAfterElect = false
		// Don't shutdown raft automatically if we renamed our hostname back to a previous name
		config.ShutdownOnRemove = false
	}

	// Build raft layer to multiplex listener.
	r.raftLayer = newRaftLayer(s.RaftListener, s.RemoteAddr)

	// Create a transport layer
	r.transport = raft.NewNetworkTransport(r.raftLayer, 3, 10*time.Second, config.LogOutput)

	// Create peer storage.
	r.peerStore = raft.NewJSONPeers(s.path, r.transport)

	peers, err := r.peerStore.Peers()
	if err != nil {
		return err
	}

	// For single-node clusters, we can update the raft peers before we start the cluster if the hostname
	// has changed.
	if config.EnableSingleNode {
		if err := r.peerStore.SetPeers([]string{s.RemoteAddr.String()}); err != nil {
			return err
		}
		peers = []string{s.RemoteAddr.String()}
	}

	// If we have multiple nodes in the cluster, make sure our address is in the raft peers or
	// we won't be able to boot into the cluster because the other peers will reject our new hostname.  This
	// is difficult to resolve automatically because we need to have all the raft peers agree on the current members
	// of the cluster before we can change them.
	if len(peers) > 0 && !raft.PeerContained(peers, s.RemoteAddr.String()) {
		s.Logger.Printf("%v is not in the list of raft peers. Please update %v/peers.json on all raft nodes to have the same contents.", s.RemoteAddr.String(), s.Path())
		return fmt.Errorf("peers out of sync: %v not in %v", s.RemoteAddr.String(), peers)
	}

	// Create the log store and stable store.
	store, err := raftboltdb.NewBoltStore(filepath.Join(s.path, "raft.db"))
	if err != nil {
		return fmt.Errorf("new bolt store: %s", err)
	}
	r.raftStore = store

	// Create the snapshot store.
	snapshots, err := raft.NewFileSnapshotStore(s.path, raftSnapshotsRetained, os.Stderr)
	if err != nil {
		return fmt.Errorf("file snapshot store: %s", err)
	}

	// Create raft log.
	ra, err := raft.NewRaft(config, (*storeFSM)(s), store, store, snapshots, r.peerStore, r.transport)
	if err != nil {
		return fmt.Errorf("new raft: %s", err)
	}
	r.raft = ra

	r.wg.Add(1)
	go r.logLeaderChanges()

	return nil
}