[KAFKA-1724] Errors after reboot in single node setup

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.8.2.0
• Fix Version/s: 0.9.0.0
• Labels: newbie
• Assignee: Harsha
• Reporter: Ciprian Hacman
• Reviewer: Jun Rao
• Created: 22/Oct/14 18:03
• Updated: 24/Feb/15 22:23
• Resolved: 24/Feb/15 22:23

Description

In a single node setup, after reboot, Kafka logs show the following:

[2014-10-22 16:37:22,206] INFO [Controller 0]: Controller starting up (kafka.controller.KafkaController)
[2014-10-22 16:37:22,419] INFO [Controller 0]: Controller startup complete (kafka.controller.KafkaController)
[2014-10-22 16:37:22,554] INFO conflict in /brokers/ids/0 data: {"jmx_port":-1,"timestamp":"1413995842465","host":"ip-10-91-142-54.eu-west-1.compute.internal","version":1,"port":9092} stored data: {"jmx_port":-1,"timestamp":"1413994171579","host":"ip-10-91-142-54.eu-west-1.compute.internal","version":1,"port":9092} (kafka.utils.ZkUtils$)
[2014-10-22 16:37:22,736] INFO I wrote this conflicted ephemeral node [{"jmx_port":-1,"timestamp":"1413995842465","host":"ip-10-91-142-54.eu-west-1.compute.internal","version":1,"port":9092}] at /brokers/ids/0 a while back in a different session, hence I will backoff for this node to be deleted by Zookeeper and retry (kafka.utils.ZkUtils$)
[2014-10-22 16:37:25,010] ERROR Error handling event ZkEvent[Data of /controller changed sent to kafka.server.ZookeeperLeaderElector$LeaderChangeListener@a6af882] (org.I0Itec.zkclient.ZkEventThread)
java.lang.IllegalStateException: Kafka scheduler has not been started
        at kafka.utils.KafkaScheduler.ensureStarted(KafkaScheduler.scala:114)
        at kafka.utils.KafkaScheduler.shutdown(KafkaScheduler.scala:86)
        at kafka.controller.KafkaController.onControllerResignation(KafkaController.scala:350)
        at kafka.controller.KafkaController$$anonfun$2.apply$mcV$sp(KafkaController.scala:162)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply$mcZ$sp(ZookeeperLeaderElector.scala:138)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply(ZookeeperLeaderElector.scala:134)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener$$anonfun$handleDataDeleted$1.apply(ZookeeperLeaderElector.scala:134)
        at kafka.utils.Utils$.inLock(Utils.scala:535)
        at kafka.server.ZookeeperLeaderElector$LeaderChangeListener.handleDataDeleted(ZookeeperLeaderElector.scala:134)
        at org.I0Itec.zkclient.ZkClient$6.run(ZkClient.java:549)
        at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)
[2014-10-22 16:37:28,757] INFO Registered broker 0 at path /brokers/ids/0 with address ip-10-91-142-54.eu-west-1.compute.internal:9092. (kafka.utils.ZkUtils$)
[2014-10-22 16:37:28,849] INFO [Kafka Server 0], started (kafka.server.KafkaServer)
[2014-10-22 16:38:56,718] INFO Closing socket connection to /127.0.0.1. (kafka.network.Processor)
[2014-10-22 16:38:56,850] INFO Closing socket connection to /127.0.0.1. (kafka.network.Processor)
[2014-10-22 16:38:56,985] INFO Closing socket connection to /127.0.0.1. (kafka.network.Processor)

The last log line repeats forever and is correlated with errors on the app side.
Restarting Kafka fixes the errors.

Steps to reproduce (with help from the mailing list):

1. start zookeeper
2. start kafka-broker
3. create topic or start a producer writing to a topic
4. stop zookeeper
5. stop kafka-broker( kafka broker shutdown goes into WARN Session
   0x14938d9dc010001 for server null, unexpected error, closing socket connection and attempting reconnect (org.apache.zookeeper.ClientCnxn) java.net.ConnectException: Connection refused)
6. kill -9 kafka-broker
7. restart zookeeper and than kafka-broker leads into the the error above

Issue Links

• duplicates: KAFKA-1596 Exception in KafkaScheduler while shutting down