[KAFKA-2818] Clean up Controller Object on forced Resignation

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.9.0.0
• Fix Version/s: 0.11.0.0
• Component/s: controller
• Assignee: Flavio Paiva Junqueira
• Reporter: Matthew Bruce
• Created: 12/Nov/15 15:54
• Updated: 01/Jun/17 19:43
• Resolved: 01/Jun/17 19:43

Description

Currently if the controller does a forced resignation (if an exception is caught during updateLeaderEpochAndSendRequest, SendUpdateMetadataRequest or shutdownBroker), the Zookeeper resignation callback function OnControllerResignation doesn't get a chance to execute which leaves some artifacts laying around. In particular the Sensors dont get cleaned up and if the Kafka broker ever gets re-elected as Controller it will fail due to some metrics already existing. An Error and stack trace of such an event is below.

A forced resignation situation can be induced with a mis-config in broker.properties fairly easily, by settig only SASL_PLAINTTEXT listeners and setting inter.broker.protocol.version=0.8.2.X

listeners=SASL_PLAINTEXT://<HOST FQDN>:9092
inter.broker.protocol.version=0.8.2.X
security.inter.broker.protocol=SASL_PLAINTEXT

[2015-11-09 16:33:47,510] ERROR Error while electing or becoming leader on broker 182050300 (kafka.server.ZookeeperLeaderElector)
java.lang.IllegalArgumentException: A metric named 'MetricName [name=connection-close-rate, group=controller-channel-metrics, description=Connections closed per second in the window., tags={broker-id=182050300}]' already exists, can't register another one.
        at org.apache.kafka.common.metrics.Metrics.registerMetric(Metrics.java:285)
        at org.apache.kafka.common.metrics.Sensor.add(Sensor.java:177)
        at org.apache.kafka.common.metrics.Sensor.add(Sensor.java:162)
        at org.apache.kafka.common.network.Selector$SelectorMetrics.<init>(Selector.java:578)
        at org.apache.kafka.common.network.Selector.<init>(Selector.java:112)
        at kafka.controller.ControllerChannelManager.kafka$controller$ControllerChannelManager$$addNewBroker(ControllerChannelManager.scala:91)
        at kafka.controller.ControllerChannelManager$$anonfun$1.apply(ControllerChannelManager.scala:43)
        at kafka.controller.ControllerChannelManager$$anonfun$1.apply(ControllerChannelManager.scala:43)
        at scala.collection.immutable.Set$Set1.foreach(Set.scala:74)
        at kafka.controller.ControllerChannelManager.<init>(ControllerChannelManager.scala:43)
        at kafka.controller.KafkaController.startChannelManager(KafkaController.scala:819)
        at kafka.controller.KafkaController.initializeControllerContext(KafkaController.scala:747)
        at kafka.controller.KafkaController.onControllerFailover(KafkaController.scala:330)
        at kafka.controller.KafkaController$$anonfun$1.apply$mcV$sp(KafkaController.scala:163)
        at kafka.server.ZookeeperLeaderElector.elect(ZookeeperLeaderElector.scala:84)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply$mcZ$sp(ZookeeperLeaderElector.scala:146)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply(ZookeeperLeaderElector.scala:141)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply(ZookeeperLeaderElector.scala:141)
        at kafka.utils.CoreUtils$.inLock(CoreUtils.scala:262)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener.handleDataDeleted(ZookeeperLeaderElector.scala:141)
        at org.I0Itec.zkclient.ZkClient$9.run(ZkClient.java:823)
        at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)

Issue Links

• relates to: KAFKA-3173 Error while moving some partitions to OnlinePartition state