From 9bd1786fe4e3d04ffa88c8cc4f4d9a30639c5be4 Mon Sep 17 00:00:00 2001
From: Xiang Li <xiang.li@coreos.com>
Date: Tue, 25 Nov 2014 15:18:40 -0800
Subject: [PATCH] raft: memory storage does not append out of date entries

---
 raft/storage.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/raft/storage.go b/raft/storage.go
index 8516bad03..4d7bd7842 100644
--- a/raft/storage.go
+++ b/raft/storage.go
@@ -182,6 +182,10 @@ func (ms *MemoryStorage) Append(entries []pb.Entry) {
 		return
 	}
 	offset := entries[0].Index - ms.snapshot.Metadata.Index
+	// do not append out of date entries
+	if offset < 0 {
+		return
+	}
 	if uint64(len(ms.ents)) >= offset {
 		ms.ents = ms.ents[:offset]
 	}