func startNode(cfg *ServerConfig, ids []types.ID) (id types.ID, n raft.Node, s *raft.MemoryStorage, w *wal.WAL) {
var err error
member := cfg.Cluster.MemberByName(cfg.Name)
metadata := pbutil.MustMarshal(
&pb.Metadata{
NodeID: uint64(member.ID),
ClusterID: uint64(cfg.Cluster.ID()),
},
)
if err := os.MkdirAll(cfg.SnapDir(), privateDirMode); err != nil {
log.Fatalf("etcdserver create snapshot directory error: %v", err)
}
if w, err = wal.Create(cfg.WALDir(), metadata); err != nil {
log.Fatalf("etcdserver: create wal error: %v", err)
}
peers := make([]raft.Peer, len(ids))
for i, id := range ids {
ctx, err := json.Marshal((*cfg.Cluster).Member(id))
if err != nil {
log.Panicf("marshal member should never fail: %v", err)
}
peers[i] = raft.Peer{ID: uint64(id), Context: ctx}
}
id = member.ID
log.Printf("etcdserver: start member %s in cluster %s", id, cfg.Cluster.ID())
s = raft.NewMemoryStorage()
n = raft.StartNode(uint64(id), peers, cfg.ElectionTicks, 1, s)
raftStatus = n.Status
return
}
func Migrate4To2(dataDir string, name string) error {
// prep new directories
sd2 := snapDir2(dataDir)
if err := os.MkdirAll(sd2, 0700); err != nil {
return fmt.Errorf("failed creating snapshot directory %s: %v", sd2, err)
}
// read v0.4 data
snap4, err := DecodeLatestSnapshot4FromDir(snapDir4(dataDir))
if err != nil {
return err
}
cfg4, err := DecodeConfig4FromFile(cfgFile4(dataDir))
if err != nil {
return err
}
ents4, err := DecodeLog4FromFile(logFile4(dataDir))
if err != nil {
return err
}
nodeIDs := ents4.NodeIDs()
nodeID := GuessNodeID(nodeIDs, snap4, cfg4, name)
if nodeID == 0 {
return fmt.Errorf("Couldn't figure out the node ID from the log or flags, cannot convert")
}
metadata := pbutil.MustMarshal(&pb.Metadata{NodeID: nodeID, ClusterID: 0x04add5})
wd2 := walDir2(dataDir)
w, err := wal.Create(wd2, metadata)
if err != nil {
return fmt.Errorf("failed initializing wal at %s: %v", wd2, err)
}
defer w.Close()
// transform v0.4 data
var snap2 *raftpb.Snapshot
if snap4 == nil {
log.Printf("No snapshot found")
} else {
log.Printf("Found snapshot: lastIndex=%d", snap4.LastIndex)
snap2 = snap4.Snapshot2()
}
st2 := cfg4.HardState2()
// If we've got the most recent snapshot, we can use it's committed index. Still likely less than the current actual index, but worth it for the replay.
if snap2 != nil && st2.Commit < snap2.Metadata.Index {
st2.Commit = snap2.Metadata.Index
}
ents2, err := Entries4To2(ents4)
if err != nil {
return err
}
ents2Len := len(ents2)
log.Printf("Found %d log entries: firstIndex=%d lastIndex=%d", ents2Len, ents2[0].Index, ents2[ents2Len-1].Index)
// set the state term to the biggest term we have ever seen,
// so term of future entries will not be the same with term of old ones.
st2.Term = ents2[ents2Len-1].Term
// explicitly prepend an empty entry as the WAL code expects it
ents2 = append(make([]raftpb.Entry, 1), ents2...)
if err = w.Save(st2, ents2); err != nil {
return err
}
log.Printf("Log migration successful")
// migrate snapshot (if necessary) and logs
var walsnap walpb.Snapshot
if snap2 != nil {
walsnap.Index, walsnap.Term = snap2.Metadata.Index, snap2.Metadata.Term
ss := snap.New(sd2)
if err := ss.SaveSnap(*snap2); err != nil {
return err
}
log.Printf("Snapshot migration successful")
}
if err = w.SaveSnapshot(walsnap); err != nil {
return err
}
return nil
}