From: Tom Pantelis <tpanteli@brocade.com>
Date: Wed, 30 Dec 2015 02:39:55 +0000 (-0500)
Subject: Bug 4850: Fix follower out-of-sync logic wrt replicatedToAllIndex
X-Git-Tag: release/lithium-sr4~9
X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=commitdiff_plain;h=957a699f85cc09b6fec9a048c6776b4d8d9d0d3b;p=controller.git

Bug 4850: Fix follower out-of-sync logic wrt replicatedToAllIndex

If the AppendEntries prevLogIndex is -1 and replicatedToAllIndex != -1,
it flags the follower as out-of-sync if there's no log entry for
replicatedToAllIndex. However replicatedToAllIndex may be in the
snapshot so I added a check for that as well. This fixes the issue
described in bug 4850.

Change-Id: If499dadc5f2a3c3823d617e60410b0f63df389d7
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>
(cherry picked from commit bb817d2b20a252f3acde329cba6ce98c592cd847)
---

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
index c8535614a9..11154e5f51 100644
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
@@ -273,7 +273,8 @@ public class Follower extends AbstractRaftActorBehavior {
                     logName(), prevLogTerm, appendEntries.getPrevLogTerm());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
                 && appendEntries.getReplicatedToAllIndex() != -1
-                && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())) {
+                && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())
+                && !context.getReplicatedLog().isInSnapshot(appendEntries.getReplicatedToAllIndex())) {
             // This append entry comes from a leader who has it's log aggressively trimmed and so does not have
             // the previous entry in it's in-memory journal
 
@@ -281,8 +282,9 @@ public class Follower extends AbstractRaftActorBehavior {
                     "{}: Cannot append entries because the replicatedToAllIndex {} does not appear to be in the in-memory journal",
                     logName(), appendEntries.getReplicatedToAllIndex());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
-                && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0 &&
-                !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)){
+                && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0
+                && !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)
+                && !context.getReplicatedLog().isInSnapshot(appendEntries.getEntries().get(0).getIndex() - 1)) {
             LOG.debug(
                     "{}: Cannot append entries because the calculated previousIndex {} was not found in the in-memory journal",
                     logName(), appendEntries.getEntries().get(0).getIndex() - 1);