【kafka】记一次kafka基于linux的原生命令的使用

环境是linux，4台机器，版本3.6，kafka安装在node 1 2 3 上，zookeeper安装在node2 3 4上。

安装好kafka，进入bin目录，可以看到有很多sh文件，是我们执行命令的基础。

启动kafka，下面的命令的后面带的配置文件的相对路径

kafka-server-start.sh ./server.properties

遇到不熟悉的sh文件，直接输入名字并回车，就会提示你可用的命令参数。如果参数用错了，kafka也会提示你相应的错误。

[root@localhost bin]# kafka-topics.sh
Create, delete, describe, or change a topic.
Option                                   Description                            
------                                   -----------                            
--alter                                  Alter the number of partitions and     replica assignment. Update the       configuration of an existing topic   via --alter is no longer supported   here (the kafka-configs CLI supports altering topic configs with a --     bootstrap-server option).            
--at-min-isr-partitions                  if set when describing topics, only    show partitions whose isr count is   equal to the configured minimum.     
--bootstrap-server <String: server to    REQUIRED: The Kafka server to connect  connect to>                              to.                                  
--command-config <String: command        Property file containing configs to be config property file>                    passed to Admin Client. This is used only with --bootstrap-server option  for describing and altering broker   configs.                             
--config <String: name=value>            A topic configuration override for the topic being created or altered. The  following is a list of valid         configurations:                      cleanup.policy                        compression.type                      delete.retention.ms                   file.delete.delay.ms                  flush.messages                        flush.ms                              follower.replication.throttled.       replicas                             index.interval.bytes                  leader.replication.throttled.replicas local.retention.bytes                 local.retention.ms                    max.compaction.lag.ms                 max.message.bytes                     message.downconversion.enable         message.format.version                message.timestamp.after.max.ms        message.timestamp.before.max.ms       message.timestamp.difference.max.ms   message.timestamp.type                min.cleanable.dirty.ratio             min.compaction.lag.ms                 min.insync.replicas                   preallocate                           remote.storage.enable                 retention.bytes                       retention.ms                          segment.bytes                         segment.index.bytes                   segment.jitter.ms                     segment.ms                            unclean.leader.election.enable        See the Kafka documentation for full   details on the topic configs. It is  supported only in combination with --create if --bootstrap-server option  is used (the kafka-configs CLI       supports altering topic configs with a --bootstrap-server option).        
--create                                 Create a new topic.                    
--delete                                 Delete a topic                         
--delete-config <String: name>           A topic configuration override to be   removed for an existing topic (see   the list of configurations under the --config option). Not supported with the --bootstrap-server option.       
--describe                               List details for the given topics.     
--exclude-internal                       exclude internal topics when running   list or describe command. The        internal topics will be listed by    default                              
--help                                   Print usage information.               
--if-exists                              if set when altering or deleting or    describing topics, the action will   only execute if the topic exists.    
--if-not-exists                          if set when creating topics, the       action will only execute if the      topic does not already exist.        
--list                                   List all available topics.             
--partitions <Integer: # of partitions>  The number of partitions for the topic being created or altered (WARNING:   If partitions are increased for a    topic that has a key, the partition  logic or ordering of the messages    will be affected). If not supplied   for create, defaults to the cluster  default.                             
--replica-assignment <String:            A list of manual partition-to-broker   broker_id_for_part1_replica1 :           assignments for the topic being      broker_id_for_part1_replica2 ,           created or altered.                  broker_id_for_part2_replica1 :                                                broker_id_for_part2_replica2 , ...>                                           
--replication-factor <Integer:           The replication factor for each        replication factor>                      partition in the topic being         created. If not supplied, defaults   to the cluster default.              
--topic <String: topic>                  The topic to create, alter, describe   or delete. It also accepts a regular expression, except for --create      option. Put topic name in double     quotes and use the '\' prefix to     escape regular expression symbols; e.g. "test\.topic".                    
--topic-id <String: topic-id>            The topic-id to describe.This is used  only with --bootstrap-server option  for describing topics.               
--topics-with-overrides                  if set when describing topics, only    show topics that have overridden     configs                              
--unavailable-partitions                 if set when describing topics, only    show partitions whose leader is not  available                            
--under-min-isr-partitions               if set when describing topics, only    show partitions whose isr count is   less than the configured minimum.    
--under-replicated-partitions            if set when describing topics, only    show under replicated partitions     
--version                                Display Kafka version.                

如这里，我们创建一个topic名为test。

kafka-topics.sh --create --topic test  --bootstrap-server node1:9092 --partitions 2 --replication-factor 2
Created topic test.

连接其中node1上的kafka获得metedata里的topic列表

[root@localhost bin]# kafka-topics.sh --list --bootstrap-server node1:9092
test

查看某个topic的细节

[root@localhost bin]# kafka-topics.sh --describe --topic test --bootstrap-server node1:9092
Topic: test	TopicId: WgjG4Ou_Q7iQvzgipRgzjg	PartitionCount: 2	ReplicationFactor: 2	Configs: Topic: test	Partition: 0	Leader: 2	Replicas: 2,1	Isr: 2,1Topic: test	Partition: 1	Leader: 3	Replicas: 3,2	Isr: 3,2

在其中的一台机器上起一个生产者，在其他两台机器上起2个消费者，都在同一个组里。

[root@localhost bin]# kafka-console-producer.sh --broker-list node1:9092 --topic test
>hello 03
>1
>2
>3
>4
>5
>6
>7
>8

可以看到同一个组内，如果组内消费者注册情况不变化有且只有同一个consumer能够消费数据。可以满足对于消息要求顺序性，不能并发消费的情况。

[root@localhost bin]# kafka-console-consumer.sh --bootstrap-server node1:9092 --topic test --group msb
hello 03
1
2
3
4
5
6
7
8

查看某个组内的情况

[root@localhost bin]# kafka-consumer-groups.sh --bootstrap-server node2:9092 --group msb --describeGROUP           TOPIC           PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG             CONSUMER-ID                                           HOST             CLIENT-ID
msb             test            1          24              24              0               console-consumer-4987804d-6e59-4f4d-9952-9afb9aff6cbe /192.168.184.130 console-consumer
msb             test            0          0               0               0               console-consumer-242992e4-7801-4a38-a8f3-8b44056ed4b6 /192.168.184.130 console-consumer

最后看一下zk中的情况吧。
zk根目录下多了一个kafka节点

[zk: localhost:2181(CONNECTED) 1] ls /
[kafka, node1, node6, node7, testLock, zookeeper]

kafka下面有很多metedata信息，包含在这些节点中，如，，

[zk: localhost:2181(CONNECTED) 2] ls /kafka
[admin, brokers, cluster, config, consumers, controller, controller_epoch, feature, isr_change_notification, latest_producer_id_block, log_dir_event_notification]
#集群id
[zk: localhost:2181(CONNECTED) 3] ls /kafka/cluster 
[id]
[zk: localhost:2181(CONNECTED) 5] get /kafka/cluster/id 
{"version":"1","id":"8t14lxoAS1SdXapY6ysw_A"}
#controller的id
[zk: localhost:2181(CONNECTED) 6] get /kafka/controller
{"version":2,"brokerid":3,"timestamp":"1698841142070","kraftControllerEpoch":-1}

可以看到topics中有一个__consumer_offsets，是kafka用来存储offset的topic。

[zk: localhost:2181(CONNECTED) 10] ls /kafka/brokers/topics 
[__consumer_offsets, test]
[zk: localhost:2181(CONNECTED) 12] get /kafka/brokers/topics/__consumer_offsets 
{"partitions":{"44":[1],"45":[2],"46":[3],"47":[1],"48":[2],"49":[3],"10":[3],"11":[1],"12":[2],"13":[3],"14":[1],"15":[2],"16":[3],"17":[1],"18":[2],"19":[3],"0":[2],"1":[3],"2":[1],"3":[2],"4":[3],"5":[1],"6":[2],"7":[3],"8":[1],"9":[2],"20":[1],"21":[2],"22":[3],"23":[1],"24":[2],"25":[3],"26":[1],"27":[2],"28":[3],"29":[1],"30":[2],"31":[3],"32":[1],"33":[2],"34":[3],"35":[1],"36":[2],"37":[3],"38":[1],"39":[2],"40":[3],"41":[1],"42":[2],"43":[3]},"topic_id":"RGxJyefAQlKrmY3LTVbKGw","adding_replicas":{},"removing_replicas":{},"version":3}