【Kafka】03 Shell 操作

查看Kafka主题列表

$KAFKA_HOME/bin/kafka-topics.sh \
--zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
--list

创建一个主题（Topic）

$KAFKA_HOME/bin/kafka-topics.sh \
--zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
--create \
--replication-factor 3 \
--partitions 1 \
--topic TOPIC-01

参数说明：

--create 参数命令：创建
--replication-factor 指定副本数量（副本数小于等于集群数）
--partitions 指定分区数量
--topic 指定主题名字

执行输出：

[root@centos7-02 ~]# $KAFKA_HOME/bin/kafka-topics.sh \
> --zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
> --create \
> --replication-factor 3 \
> --partitions 1 \
> --topic TOPIC-01
OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
Created topic "TOPIC-01".

删除主题

$KAFKA_HOME/bin/kafka-topics.sh \
--zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
--delete \
--topic TOPIC-01

向主题发送消息和消费消息

窗口1发送

# 发送消息 (终端占用)
$KAFKA_HOME/bin/kafka-console-producer.sh \
--broker-list centos7-02:9092,centos7-03:9092,centos7-04:9092 \
--topic TOPIC-01

窗口2消费

# 消费消息
$KAFKA_HOME/bin/kafka-console-consumer.sh \
--bootstrap-server centos7-02:9092,centos7-03:9092,centos7-04:9092 \
--topic TOPIC-01

全部获取消费

# 消费消息 格式3
# --from-beginning：会把主题中以往所有的数据都读取出来。
$KAFKA_HOME/bin/kafka-console-consumer.sh \
--bootstrap-server centos7-02:9092,centos7-03:9092,centos7-04:9092 \
--from-beginning \
--topic TOPIC-01

查看具体主题的状态：

$KAFKA_HOME/bin/kafka-topics.sh \
--zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
--describe \
--topic TOPIC-01

执行输出：

[root@centos7-02 ~]# $KAFKA_HOME/bin/kafka-topics.sh \
> --zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
> --describe \
> --topic TOPIC-01
OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
Topic:TOPIC-01    PartitionCount:1    ReplicationFactor:3    Configs:
    Topic: TOPIC-01    Partition: 0    Leader: 1    Replicas: 1,2,0    Isr: 1,2,0

更改主题的分区数量

$KAFKA_HOME/bin/kafka-topics.sh \
--zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
--alter \
--partitions 2 \
--topic TOPIC-01

执行输出：

[root@centos7-02 ~]# $KAFKA_HOME/bin/kafka-topics.sh \
> --zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
> --alter \
> --partitions 2 \
> --topic TOPIC-01
OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
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!

注意，分区的数量只能增加，不能减少，改小了报错

改小的执行输出：

[root@centos7-02 ~]# $KAFKA_HOME/bin/kafka-topics.sh \
> --zookeeper centos7-02:2181,centos7-03:2181,centos7-04:2181 \
> --alter \
> --partitions 1 \
> --topic TOPIC-01
OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
WARNING: If partitions are increased for a topic that has a key, the partition logic or ordering of the messages will be affected
Error while executing topic command : The number of partitions for a topic can only be increased. Topic TOPIC-01 currently has 2 partitions, 1 would not be an increase.
[2022-01-31 16:14:02,014] ERROR org.apache.kafka.common.errors.InvalidPartitionsException: The number of partitions for a topic can only be increased. Topic TOPIC-01 currently has 2 partitions, 1 would not be an increase.
 (kafka.admin.TopicCommand$)