From 771ee43169293aab94110b9014cf802f411ec734 Mon Sep 17 00:00:00 2001 From: Xiang Li Date: Tue, 30 Aug 2016 10:43:36 -0700 Subject: [PATCH] etcdserver: allow zero kv index for cluster upgrade If a user upgrades etcd from 2.3.x to 3.0 and shutdown the cluster immediately without triggering any new backend writes, then the consistent index in backend would be zero. The user cannot restart etcdserver due to today's strick index match checking. We now have to lose this a bit for this case. --- etcdserver/server.go | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/etcdserver/server.go b/etcdserver/server.go index 077ac7d69..055f71298 100644 --- a/etcdserver/server.go +++ b/etcdserver/server.go @@ -408,8 +408,13 @@ func NewServer(cfg *ServerConfig) (srv *EtcdServer, err error) { srv.kv = mvcc.New(srv.be, srv.lessor, &srv.consistIndex) if beExist { kvindex := srv.kv.ConsistentIndex() + // TODO: remove kvindex != 0 checking when we do not expect users to upgrade + // etcd from pre-3.0 release. if snapshot != nil && kvindex < snapshot.Metadata.Index { - return nil, fmt.Errorf("database file (%v index %d) does not match with snapshot (index %d).", bepath, kvindex, snapshot.Metadata.Index) + if kvindex != 0 { + return nil, fmt.Errorf("database file (%v index %d) does not match with snapshot (index %d).", bepath, kvindex, snapshot.Metadata.Index) + } + plog.Warningf("consistent index never saved (snapshot index=%d)", snapshot.Metadata.Index) } } srv.consistIndex.setConsistentIndex(srv.kv.ConsistentIndex())