randomize based on self address

fix #851

weed/server/raft_server.go

@@ -14,6 +14,7 @@ import (
 	"github.com/chrislusf/raft"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/topology"
+	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/gorilla/mux"
 )
 
@@ -71,6 +72,7 @@ func NewRaftServer(r *mux.Router, peers []string, httpAddr string, dataDir strin
 	for _, peer := range s.peers {
 		s.raftServer.AddPeer(peer, "http://"+peer)
 	}
+	rand.Seed(util.HashBytesToInt64([]byte(httpAddr)))
 	time.Sleep(time.Duration(1000+rand.Int31n(3000)) * time.Millisecond)
 	if s.raftServer.IsLogEmpty() {
 		// Initialize the server by joining itself.

weed/util/randomizer.go

@@ -0,0 +1,9 @@
+package util
+
+import "hash/fnv"
+
+func HashBytesToInt64(x []byte) int64 {
+	hash := fnv.New64()
+	hash.Write(x)
+	return int64(hash.Sum64())
+}