Kafka的使用和错误解决

爱是王道

　　Kafka的使用和错误解决
　　一、下载kafka解压缩：配置环境变量

vim /etc/profile
export KAFKA_HOME=/root/kafka_2.11-1.0.0
export PATH=$PATH:$KAFKA_HOME/bin
source /etc/profile
　　二 、kafka中需要使用zookeeper

（一）使用kafka自带的zookeeper

• 　　先将zookeeper启动,如果在伪分布式下,kafka已经集成了zk，在kafka中的config目录下。
  
     可以编辑config/zookeeper.properties修改zookeeper的端口号。
  　　后台启动zookeeper：  
  [root@mail bin]# nohup zookeeper-server-start.sh ../config/zookeeper.properties &
  
  
• 启动broker
  

`[root@mail bin]# nohup kafka-server-start.sh ../config/server.properties &`
　　3.测试:模拟消息的消费和生产
　　（1）创建主题

[root@mail bin]# kafka-topics.sh --create --zookeeper localhost:2281 --topic KafkaTestTopic --partitions 1 --replication-factor 1
Created topic "KafkaTestTopic".
　　（2）创建生产者

[root@mail bin]# kafka-console-producer.sh --topic KafkaTestTopic --broker-list localhost:9092
　　查看server.properties中的#listeners=PLAINTEXT://:9092，获取kafka的端口
　　（3）创建消费者

[root@mail bin]# kafka-console-consumer.sh --topic KafkaTestTopic --zookeeper localhost:2281
　　（二）使用非kafka自带的zookeeper

使用zookeeper（非kafka自带）
[root@mail zookeeper-3.4.10]# bin/zkServer.sh start conf/zoo.cfg
ZooKeeper JMX enabled by default
Using config: conf/zoo.cfg
Starting zookeeper ... STARTED
（1） 创建主题
[root@mail kafka_2.11-1.0.0]# bin/kafka-topics.sh --create --zookeeper localhost:2181 --topic secondTopic --partitions 1 --replication-factor 1
Created topic "secondTopic".
（2）kafka启动
[root@mail kafka_2.11-1.0.0]# nohup bin/kafka-server-start.sh config/server.properties &
（3）kafka生产者
[root@mail kafka_2.11-1.0.0]# kafka-console-producer.sh --topic KafkaTestTopic --broker-list localhost:9092
（4）kafka消费者
[root@mail kafka_2.11-1.0.0]#  bin/kafka-console-consumer.sh --topic KafkaTestTopic --zookeeper localhost:2181
Using the ConsoleConsumer with old consumer is deprecated and will be removed in a future major release. Consider using the new consumer by passing [bootstrap-server] instead of [zookeeper].
（5）查看kafka中的数据
[root@mail kafka_2.11-1.0.0]# ls
bin  config  libs  LICENSE  logs  logs-kafka  nohup.out  NOTICE  site-docs
[root@mail kafka_2.11-1.0.0]# cd logs-kafka/             #kafka中的数据存储目录
##这个目录是在kafka的config/server.properties文件中进行配置的
log.dirs=/root/kafka/kafka_2.11-1.0.0/logs-kafka
[root@mail logs-kafka]# ls             #查看kafka中的主题
cleaner-offset-checkpoint  __consumer_offsets-20  __consumer_offsets-33  __consumer_offsets-46  kafka_test-0
__consumer_offsets-0       __consumer_offsets-21  __consumer_offsets-34  __consumer_offsets-47  KafkaTestTopic-0
__consumer_offsets-1       __consumer_offsets-22  __consumer_offsets-35  __consumer_offsets-48  log-start-offset-checkpoint
__consumer_offsets-10      __consumer_offsets-23  __consumer_offsets-36  __consumer_offsets-49  meta.properties
__consumer_offsets-11      __consumer_offsets-24  __consumer_offsets-37  __consumer_offsets-5   My_LOVE_TOPIC-0
__consumer_offsets-12      __consumer_offsets-25  __consumer_offsets-38  __consumer_offsets-6   mytopic-0
__consumer_offsets-13      __consumer_offsets-26  __consumer_offsets-39  __consumer_offsets-7   recovery-point-offset-checkpoint
__consumer_offsets-14      __consumer_offsets-27  __consumer_offsets-4   __consumer_offsets-8   replication-offset-checkpoint
__consumer_offsets-15      __consumer_offsets-28  __consumer_offsets-40  __consumer_offsets-9   stock-quotation-0
__consumer_offsets-16      __consumer_offsets-29  __consumer_offsets-41  hello-0                stock-quotation-avro-0
__consumer_offsets-17      __consumer_offsets-3   __consumer_offsets-42  hello-1                stock-quotation-partition-0
__consumer_offsets-18      __consumer_offsets-30  __consumer_offsets-43  hello-2                TEST-TOPIC-0
__consumer_offsets-19      __consumer_offsets-31  __consumer_offsets-44  hello-3
__consumer_offsets-2       __consumer_offsets-32  __consumer_offsets-45  hello-4
[root@mail logs-kafka]# cd KafkaTestTopic-0/       #查看kakfa的主题为KafkaTestTopic的0号分区
[root@mail KafkaTestTopic-0]# ls
00000000000000000000.index  00000000000000000000.timeindex  leader-epoch-checkpoint
00000000000000000000.log    00000000000000000063.snapshot
[root@mail KafkaTestTopic-0]# tail -f 000000000000000000.log      #kafka中的数据存储文件
（6）修改kafka的分区数,观察kafka的变化
## 修改kafka分区数
[root@mail kafka_2.11-1.0.0]# bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic KafkaTestTopic --partitions 3
WARNING: If partitions are increased for a topic that has a key, the partition logic or ordering of the messages will be affected
Adding partitions succeeded!
[root@mail kafka_2.11-1.0.0]# ls
bin  config  libs  LICENSE  logs  logs-kafka  nohup.out  NOTICE  site-docs
[root@mail kafka_2.11-1.0.0]# cd logs-kafka/
#发现出现kakfa的主题为KafkaTestTopic的0号分区,1号分区,2号分区,总共3个分区
[root@mail logs-kafka]# ls
cleaner-offset-checkpoint  __consumer_offsets-20  __consumer_offsets-33  __consumer_offsets-46  kafka_test-0
__consumer_offsets-0       __consumer_offsets-21  __consumer_offsets-34  __consumer_offsets-47  KafkaTestTopic-0
__consumer_offsets-1       __consumer_offsets-22  __consumer_offsets-35  __consumer_offsets-48  KafkaTestTopic-1
__consumer_offsets-10      __consumer_offsets-23  __consumer_offsets-36  __consumer_offsets-49  KafkaTestTopic-2
__consumer_offsets-11      __consumer_offsets-24  __consumer_offsets-37  __consumer_offsets-5   log-start-offset-checkpoint
__consumer_offsets-12      __consumer_offsets-25  __consumer_offsets-38  __consumer_offsets-6   meta.properties
__consumer_offsets-13      __consumer_offsets-26  __consumer_offsets-39  __consumer_offsets-7   My_LOVE_TOPIC-0
__consumer_offsets-14      __consumer_offsets-27  __consumer_offsets-4   __consumer_offsets-8   mytopic-0
__consumer_offsets-15      __consumer_offsets-28  __consumer_offsets-40  __consumer_offsets-9   recovery-point-offset-checkpoint
__consumer_offsets-16      __consumer_offsets-29  __consumer_offsets-41  hello-0                replication-offset-checkpoint
__consumer_offsets-17      __consumer_offsets-3   __consumer_offsets-42  hello-1                stock-quotation-0
__consumer_offsets-18      __consumer_offsets-30  __consumer_offsets-43  hello-2                stock-quotation-avro-0
__consumer_offsets-19      __consumer_offsets-31  __consumer_offsets-44  hello-3                stock-quotation-partition-0
__consumer_offsets-2       __consumer_offsets-32  __consumer_offsets-45  hello-4                TEST-TOPIC-0
[root@mail KafkaTestTopic-1]# ls                  #查看kakfa的主题为KafkaTestTopic的1号分区
00000000000000000000.index  00000000000000000000.log  00000000000000000000.timeindex  leader-epoch-checkpoint
[root@mail KafkaTestTopic-1]# tail -f 00000000000000000000.log
　　三、可能出现的错误：
（1）
[root@mail bin]# kafka-topics.sh --create --zookeeper localhost:2281 --topic KafkaTestTopic --partitions 1 --replication-factor 1
Error while executing topic command : Replication factor: 1 larger than available brokers: 0.
[2018-11-20 16:44:16,269] ERROR org.apache.kafka.common.errors.InvalidReplicationFactorException: Replication factor: 1 larger than available brokers: 0.
(kafka.admin.TopicCommand$)
　　解决：修改server.properties中的：zookeeper.connect=localhost:2281，让2281端口号和zookeeper.properties中的zookeeper端口号一致，然后重启kafka。**
　　（2）
kafka.common.KafkaException: fetching topic metadata for topics [Set(KafkaTestTopic)] from broker [ArrayBuffer(BrokerEndPoint(0,123.125.50.7,9092))] failed
at kafka.client.ClientUtils$.fetchTopicMetadata(ClientUtils.scala:77)
at kafka.client.ClientUtils$.fetchTopicMetadata(ClientUtils.scala:98)
at kafka.consumer.ConsumerFetcherManager$LeaderFinderThread.doWork(ConsumerFetcherManager.scala:67)
（3）
[2018-11-20 17:28:53,411] WARN [Producer clientId=console-producer] Error while fetching metadata with correlation id 52 : {KafkaTestTopic=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2018-11-20 17:28:53,513] WARN [Producer clientId=console-producer] Error while fetching metadata with correlation id 53 : {KafkaTestTopic=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2018-11-20 17:28:53,617] WARN [Producer clientId=console-producer] Error while fetching metadata with correlation id 54 : {KafkaTestTopic=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2018-11-20 17:28:53,721] WARN [Producer clientId=console-producer] Error while fetching metadata with correlation id 55 : {KafkaTestTopic=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
　　解决(2)和（3)的错误:
修改server.properties中的
I、listeners=PLAINTEXT://localhost:9092
II、 advertised.listeners=PLAINTEXT://localhost:9092
　　(4)  [2018-11-29 09:44:35,275] WARN [Producer clientId=console-producer] Connection to node -1 could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
　　解决：可能的原因：kafka未启动，重启启动kafka。
　　kafka中查看zookeeper状态：
　　bin/zookeeper-shell.sh localhost:2181