Clear leaderId when election timeout occurs in non-voting follower

[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / behaviors / Follower.java

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 7e6654d5d6b9849b106a36bf56c76928798d912d..d484b25626155b48964a91b6be46fb7230a40932 100644 (file)
--- 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
@@ -11,8 +11,8 @@ package org.opendaylight.controller.cluster.raft.behaviors;
 import akka.actor.ActorRef;
 import akka.japi.Procedure;
 import com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Preconditions;
 import java.util.ArrayList;
+import javax.annotation.Nullable;
 import org.opendaylight.controller.cluster.raft.RaftActorContext;
 import org.opendaylight.controller.cluster.raft.RaftState;
 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
@@ -65,12 +65,10 @@ public class Follower extends AbstractRaftActorBehavior {
 
         initialSyncStatusTracker = new SyncStatusTracker(context.getActor(), getId(), SYNC_THRESHOLD);
 
-        if(canStartElection()) {
-            if (context.getPeerIds().isEmpty() && getLeaderId() == null) {
-                actor().tell(ElectionTimeout.INSTANCE, actor());
-            } else {
-                scheduleElection(electionDuration());
-            }
+        if (context.getPeerIds().isEmpty() && getLeaderId() == null) {
+            actor().tell(ElectionTimeout.INSTANCE, actor());
+        } else {
+            scheduleElection(electionDuration());
         }
     }
 
@@ -80,8 +78,8 @@ public class Follower extends AbstractRaftActorBehavior {
     }
 
     @VisibleForTesting
-    protected final void setLeaderId(final String leaderId) {
-        this.leaderId = Preconditions.checkNotNull(leaderId);
+    protected final void setLeaderId(@Nullable final String leaderId) {
+        this.leaderId = leaderId;
     }
 
     @Override
@@ -95,7 +93,7 @@ public class Follower extends AbstractRaftActorBehavior {
     }
 
     private boolean isLogEntryPresent(long index){
-        if(index == context.getReplicatedLog().getSnapshotIndex()){
+        if(context.getReplicatedLog().isInSnapshot(index)) {
             return true;
         }
 
@@ -299,8 +297,8 @@ public class Follower extends AbstractRaftActorBehavior {
             // The follower's log is out of sync because the Leader's
             // prevLogIndex entry was not found in it's log
 
-            LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it",
-                        logName(), appendEntries.getPrevLogIndex());
+            LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it - lastIndex: {}, snapshotIndex: {}",
+                        logName(), appendEntries.getPrevLogIndex(), lastIndex, context.getReplicatedLog().getSnapshotIndex());
         } else if (lastIndex > -1 && prevEntryPresent && prevLogTerm != appendEntries.getPrevLogTerm()) {
 
             // The follower's log is out of sync because the Leader's
@@ -312,8 +310,7 @@ public class Follower extends AbstractRaftActorBehavior {
                     logName(), prevLogTerm, appendEntries.getPrevLogTerm());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
                 && appendEntries.getReplicatedToAllIndex() != -1
-                && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())
-                && !context.getReplicatedLog().isInSnapshot(appendEntries.getReplicatedToAllIndex())) {
+                && !isLogEntryPresent(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
 
@@ -322,8 +319,7 @@ public class Follower extends AbstractRaftActorBehavior {
                     logName(), appendEntries.getReplicatedToAllIndex());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
                 && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0
-                && !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)
-                && !context.getReplicatedLog().isInSnapshot(appendEntries.getEntries().get(0).getIndex() - 1)) {
+                && !isLogEntryPresent(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);
@@ -352,6 +348,8 @@ public class Follower extends AbstractRaftActorBehavior {
                 LOG.debug("{}: Received ElectionTimeout - switching to Candidate", logName());
                 return internalSwitchBehavior(RaftState.Candidate);
             } else {
+                setLeaderId(null);
+                scheduleElection(electionDuration());
                 return this;
             }
         }
@@ -413,7 +411,7 @@ public class Follower extends AbstractRaftActorBehavior {
                         installSnapshot.getLastIncludedTerm(),
                         context.getTermInformation().getCurrentTerm(),
                         context.getTermInformation().getVotedFor(),
-                        context.getPeerServerInfo(true));
+                        installSnapshot.getServerConfig().orNull());
 
                 ApplySnapshot.Callback applySnapshotCallback = new ApplySnapshot.Callback() {
                     @Override