CDH中安装Kafka基本指令总结——topic使用与测试producer产生数据、consumer消费数据
这里主要总结一些我在CDH中安装的kafka测试的一些比较基础的指令。
一、相关基础内容
Kafka群集中的每个主机都运行一个称为代理的服务器，该服务器存储发送到主题的消息并服务于消费者请求。
首先先看服务器安装kafka的实例信息：
注意：
然后正常kafka的指令是 ： ./bin/kafka-topics.sh --zookeeper cluster2-4:2181 .......
但是使用CDH安装的kafka则不需要全写出此 ./bin/kafka-topics.sh 部分。只许直接写 kafka-topics 即可，这是很重要的一个区别，使用CDH安装的kafka时候要特别注意一下。
具体有哪些指令可以看此路径下：
/opt/cloudera/parcels/KAFKA-4.1.0-1.4.1.0.p0.4/bin
二、topic主题使用
接下来测试topic指令，这里我们要先看CDH中配置的这个ZooKeeper Root的Kafka服务范围为: " /kafka "。
所以我们使用topic的指令格式应该都类似：
kafka-topics --zookeeper cluster2-4:2181/kafka ......
A.创建一个名为 test 的主题（Topic）：
kafka-topics --zookeeper cluster2-4:2181/kafka --create -replication-factor 1 --partitions 3 --topic test
Or
若是上述中的 ZooKeeper Root 的Kafka服务范围为: " / "。则这里的创建主题指令改为：
kafka-topics --zookeeper cluster2-4:2181 --create --replication-factor 1 --partitions 3 --topic testB.查询现在已经存在的topic：
kafka-topics --zookeeper localhost:2181/kafka --list
C.删除创建的topic：
kafka-topics --zookeeper localhost:2181/kafka --delete --topic test2
拓展：
这里如果直接删除，则会输出 Topic *** is marked for deletion 如上图，如果我们topic中消息堆积的太多，或者kafka所在磁盘空间满了等等，则会需要彻底清理一下kafka topic。
方法一：修改kafaka配置文件server.properties， 添加 delete.topic.enable=true，重启kafka，之后通过kafka命令行就可以直接删除topic。
方法二：通过命令行删除topic： ./bin/kafka-topics.sh --delete --zookeeper {zookeeper server} --topic {topic name}
因为kafaka配置文件中server.properties没有配置delete.topic.enable=true，此时的删除并不是真正的删除，只是把topic标记为：marked for deletion 你可以通过命令：./bin/kafka-topics --zookeeper {zookeeper server} --list 来查看所有topic
方法三：若需要真正删除它，需要登录zookeeper客户端：
zookeeper-client找到topic所在的目录：
ls /kafka/brokers/topics执行命令，即可，此时topic被彻底删除：
rmr /kafka/brokers/topics/{topic name}D.修改topic的分区数：
kafka-topics --zookeeper localhost:2181/kafka --alter --topic test \ partitions 5
E.查看topic的详细信息：
kafka-topics --describe --zookeeper localhost:2181/kafka --topic test
F.我们还可以在这里测试分布式是否连接正常：
kafka-topics --zookeeper cluster2-4:2181/kafka --list
kafka-topics --zookeeper cluster2-3:2181/kafka --list
可以看到在2-4这台服务器中，我们后面输入 cluster2-4:2181/kafka 与 cluster2-3:2181/kafka 均可得到统一的信息。
topic指令参数：
Option Description
------ -----------
--alter Alter the number of partitions,
replica assignment, and/or
configuration for the topic.
--bootstrap-server to. In case of providing this, a
direct Zookeeper connection won't be
required.
--command-config passed to Admin Client. This is used
only with --bootstrap-server option
for describing and altering broker
configs.
--config 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
max.message.bytes
message.downconversion.enable
message.format.version
message.timestamp.difference.max.ms
message.timestamp.type
min.cleanable.dirty.ratio
min.compaction.lag.ms
min.insync.replicas
preallocate
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.
--create Create a new topic.
--delete Delete a topic
--delete-config 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.
--disable-rack-aware Disable rack aware replica assignment
--exclude-internal exclude internal topics when running
list or describe command. The
internal topics will be listed by
default
--force Suppress console prompts
--help Print usage information.
--if-exists if set when altering or deleting or
describing topics, the action will
only execute if the topic exists.
Not supported with the --bootstrap-
server option.
--if-not-exists if set when creating topics, the
action will only execute if the
topic does not already exist. Not
supported with the --bootstrap-
server option.
--list List all available topics.
--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
--replica-assignment
--replication-factor partition in the topic being created.
--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".
--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-replicated-partitions if set when describing topics, only
show under replicated partitions
--zookeeper DEPRECATED, The connection string for
the zookeeper connection in the form
host:port. Multiple hosts can be
given to allow fail-over. 三、测试producer产生数据、consumer消费数据
之前我们创建好topic以后，这里测试一下如何使用kafka中的kafka-console-producer与kafka-console-consumer来生产数据、另一端消费数据。
还需先了解这里 发布-订阅系统中的代理结构：
producer产生数据到Topic中，然后consumer从要消费的Topic中消费数据。
- 首先启动producer：
kafka-console-producer --broker-list cluster2-4:9092 --topic test
- 在这里输入数据，这些数据会上传到zookeeper中的 /kafka/broker/test 主题中。
kafka-console-producer 生产者的指令参数：
Option Description
------ -----------
--batch-size Number of messages to send in a single
batch if they are not being sent
synchronously. (default: 200)
--broker-list REQUIRED: The broker list string in
the form HOST1:PORT1,HOST2:PORT2.
--compression-codec [String: The compression codec: either 'none',
compression-codec] 'gzip', 'snappy', 'lz4', or 'zstd'.
If specified without value, then it
defaults to 'gzip'
--help Print usage information.
--line-reader The class name of the class to use for
reading lines from standard in. By
default each line is read as a
separate message. (default: kafka.
tools.
ConsoleProducer$LineMessageReader)
--max-block-ms block for during a send request
(default: 60000)
--max-memory-bytes to buffer records waiting to be sent
to the server. (default: 33554432)
--max-partition-memory-bytes partition. When records are received
which are smaller than this size the
producer will attempt to
optimistically group them together
until this size is reached.
(default: 16384)
--message-send-max-retries Brokers can fail receiving the message
for multiple reasons, and being
unavailable transiently is just one
of them. This property specifies the
number of retires before the
producer give up and drop this
message. (default: 3)
--metadata-expiry-ms after which we force a refresh of
metadata even if we haven't seen any
leadership changes. (default: 300000)
--producer-property properties in the form key=value to
the producer.
--producer.config Producer config properties file. Note
that [producer-property] takes
precedence over this config.
--property A mechanism to pass user-defined
properties in the form key=value to
the message reader. This allows
custom configuration for a user-
defined message reader.
--request-required-acks requests (default: 1)
--request-timeout-ms requests. Value must be non-negative
and non-zero (default: 1500)
--retry-backoff-ms Before each retry, the producer
refreshes the metadata of relevant
topics. Since leader election takes
a bit of time, this property
specifies the amount of time that
the producer waits before refreshing
the metadata. (default: 100)
--socket-buffer-size The size of the tcp RECV size.
(default: 102400)
--sync If set message send requests to the
brokers are synchronously, one at a
time as they arrive.
--timeout If set and the producer is running in
asynchronous mode, this gives the
maximum amount of time a message
will queue awaiting sufficient batch
size. The value is given in ms.
(default: 1000)
--topic REQUIRED: The topic id to produce
messages to. - 接着启动消费者：
kafka-console-consumer --bootstrap-server cluster2-3:9092 --topic test --from-beginning
后面的 --from-beginning 表示从指定主题中有效的起始位移位置开始消费所有分区的消息。
- 消费者消费到topic的数据：
kafka-console-consumer 消费者的指令参数：
Option Description
------ -----------
--bootstrap-server
--consumer-property properties in the form key=value to
the consumer.
--consumer.config Consumer config properties file. Note
that [consumer-property] takes
precedence over this config.
--enable-systest-events Log lifecycle events of the consumer
in addition to logging consumed
messages. (This is specific for
system tests.)
--formatter The name of a class to use for
formatting kafka messages for
display. (default: kafka.tools.
DefaultMessageFormatter)
--from-beginning If the consumer does not already have
an established offset to consume
from, start with the earliest
message present in the log rather
than the latest message.
--group The consumer group id of the consumer.
--help Print usage information.
--isolation-level Set to read_committed in order to
filter out transactional messages
which are not committed. Set to
read_uncommittedto read all
messages. (default: read_uncommitted)
--key-deserializer
--max-messages The maximum number of messages to
consume before exiting. If not set,
consumption is continual.
--offset The offset id to consume from (a non-
negative number), or 'earliest'
which means from beginning, or
'latest' which means from end
(default: latest)
--partition The partition to consume from.
Consumption starts from the end of
the partition unless '--offset' is
specified.
--property The properties to initialize the
message formatter. Default
properties include:
print.timestamp=true|false
print.key=true|false
print.value=true|false
key.separator=
line.separator=
key.deserializer=
value.deserializer=
Users can also pass in customized
properties for their formatter; more
specifically, users can pass in
properties keyed with 'key.
deserializer.' and 'value.
deserializer.' prefixes to configure
their deserializers.
--skip-message-on-error If there is an error when processing a
message, skip it instead of halt.
--timeout-ms If specified, exit if no message is
available for consumption for the
specified interval.
--topic The topic id to consume on.
--value-deserializer
--whitelist Regular expression specifying
whitelist of topics to include for
consumption.