[KAFKA-6682] Kafka reconnection after broker restart

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 1.0.0
• Component/s: clients
• Assignee: Unassigned
• Reporter: madi
• Created: 19/Mar/18 13:50
• Updated: 17/May/18 18:05
• Resolved: 17/May/18 18:05

Description

I am using kafka producer plugin for logback (danielwegener) with the clients library 1.0.0 and after restart of broker all my JVMs connected to it get tons of the exceptions:

11:22:48.738 [kafka-producer-network-thread | app-logback-relaxed] cid: 
clid: E [        @] a: o.a.k.c.p.internals.Sender - [Producer 
clientId=id-id-logback-relaxed] Uncaught error in kafka producer I/O 
thread:  ex:java.lang.NullPointerException: null
    at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:436)
    at org.apache.kafka.common.network.Selector.poll(Selector.java:399)
    at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:460)
    at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:239)
    at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:163)
    at java.lang.Thread.run(Thread.java:798)

During restart there are still other brokers available behind LB.   

Dosen't matter kafka is up again, only restarting JVM helps

    <appender name="kafkaLogAppender" class="com.github.danielwegener.logback.kafka.KafkaAppender">
                <!-- This is the default encoder that encodes every log message to an utf8-encoded string  -->
            <encoder>
                   
 <pattern>%date{"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"} ${HOSTNAME} 
[%thread] %logger{32} - %message ex:%exf%n</pattern>
            </encoder>
            <topic>mytopichere</topic>
                <!-- we don't care how the log messages will be partitioned  -->
            <keyingStrategy class="com.github.danielwegener.logback.kafka.keying.HostNameKeyingStrategy" />
                <!-- use async delivery. the application threads are not blocked by logging -->
            <deliveryStrategy class="com.github.danielwegener.logback.kafka.delivery.AsynchronousDeliveryStrategy" />
                <!-- each <producerConfig> translates to regular kafka-client config (format: key=value) -->
               
 <!-- producer configs are documented here: 
https://kafka.apache.org/documentation.html#newproducerconfigs -->
                <!-- bootstrap.servers is the only mandatory producerConfig -->
            <producerConfig>bootstrap.servers=10.99.99.1:9092</producerConfig>
                <!-- don't wait for a broker to ack the reception of a batch.  -->
            <producerConfig>acks=0</producerConfig>
                <!-- even if the producer buffer runs full, do not block the application but start to drop messages -->
            <producerConfig>block.on.buffer.full=false</producerConfig>
                <!-- define a client-id that you use to identify yourself against the kafka broker -->
            <producerConfig>client.id=${HOSTNAME}-${CONTEXT_NAME}-logback-relaxed</producerConfig>
                <!-- use gzip to compress each batch of log messages. valid values: none, gzip, snappy  -->
                <!-- do przetestowania narzut -->
            <producerConfig>compression.type=none</producerConfig>
               
 <!-- there is no fallback <appender-ref>. If this appender 
cannot deliver, it will drop its messages. -->
            <producerConfig>max.block.ms=0</producerConfig>
    </appender>

I provide loadbalancer address in bootstrap servers here. There are three kafka brokers behind.

java version "1.7.0"
Java(TM) SE Runtime Environment (build pap6470sr9fp60ifix-20161110_01(SR9 FP60)+IV90630+IV90578))
IBM J9 VM (build 2.6, JRE 1.7.0 AIX ppc64-64 Compressed References 20161005_321282 (JIT enabled, AOT enabled)
J9VM - R26_Java726_SR9_20161005_1259_B321282
JIT  - tr.r11_20161001_125404
GC   - R26_Java726_SR9_20161005_1259_B321282_CMPRSS
J9CL - 20161005_321282)
JCL - 20161021_01 based on Oracle jdk7u121-b15