开始上手：
1，官网下载地址
2，按照官网的方式quickstart（解压、启动、通信）
3，需要注意的是:
1、kafka自带zookeeper，需要先启动zookeeper，再启动kafka。
2、kafka版本差异较大，不同版本命令不同；
3、后台启动方式：bin/kafka-server-start.sh -daemon ./config/server.properties
4、若zookeeper在其它服务器，可设置ip连接.
5、监听，设置为本机ip。 listeners=PLAINTEXT://192.168.1.103:9092 （监听）
4，使用自己的zookeeper服务器：
a,在另外一台服务器安装zookeeper并启动。
b,修改kafka配置文件config/server.properties,指定zk服务器的IP地址
zookeeper.connect=192.168.1.110:2181
c,保存并启动Kafka。
Kafka配置详解
# Licensed to the Apache Software Foundation (ASF) under one or more # contributor license agreements. See the NOTICE file distributed with # this work for additional information regarding copyright ownership. # The ASF licenses this file to You under the Apache License, Version 2.0 # (the "License"); you may not use this file except in compliance with # the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # see kafka.server.KafkaConfig for additional details and defaults ############################# Server Basics ############################# # The id of the broker. This must be set to a unique integer for each broker. #Broker的ID，每个broker必须又有唯一的值。 broker.id=1 ############################# Socket Server Settings ############################# # The address the socket server listens on. It will get the value returned from # java.net.InetAddress.getCanonicalHostName() if not configured. # FORMAT: # listeners = listener_name://host_name:port # EXAMPLE: # listeners = PLAINTEXT://your.host.name:9092
#listeners就是主要用来定义Kafka Broker的Listener的配置项。 #Socket服务器监听的地址，如果没有设置，则监听java.net.InetAddress.getCanonicalHostName()返回的地址 listeners=PLAINTEXT://172.16.3.177:9092 # Hostname and port the broker will advertise to producers and consumers. If not set, # it uses the value for "listeners" if configured. Otherwise, it will use the value # returned from java.net.InetAddress.getCanonicalHostName(). #broker通知到producers和consumers的主机地址和端口号。如果未设置，使用listeners的配置。 #否则，使用java.net.InetAddress#.getCanonicalHostName()返回的值。 #如果均为设置，拿到的值为localhot:9092,将造成无法连接其他机器 #advertised.listeners=PLAINTEXT://your.host.name:9092 # Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details #listener名称到安全协议。默认所有的listener使用相同的安全协议。PLAINTEXT为明码文本协议 #listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL # The number of threads that the server uses for receiving requests from the network and sending responses to the network #服务器用来从网络接收请求和发送响应数据到网络的线程数 num.network.threads=3 # The number of threads that the server uses for processing requests, which may include disk I/O #服务器用来处理请求的线程数，可能包含磁盘I/O的线程。 num.io.threads=8 # The send buffer (SO_SNDBUF) used by the socket server #服务器发送数据的缓存大小。 socket.send.buffer.bytes=102400 # The receive buffer (SO_RCVBUF) used by the socket server #服务器接收数据的缓存大小。 socket.receive.buffer.bytes=102400 # The maximum size of a request that the socket server will accept (protection against OOM) #socket服务器接收的单个request大小的最大值。 socket.request.max.bytes=104857600 #Kafka的数据都是存储在log文件中的，log的配置即是data的配置 ############################# Log Basics ############################# #Log 基本设置： # A comma separated list of directories under which to store log files #Kafka存储log文件的目录，多个目录用逗号分隔。 log.dirs=/home/logs/kafka # The default number of log partitions per topic. More partitions allow greater # parallelism for consumption, but this will also result in more files across # the brokers. #topic的默认分割的分区个数。多分区允许消费者并行获取数据，但这也会造成brokers交叉保存多个文件。 num.partitions=10 # The number of threads per data directory to be used for log recovery at startup and flushing at shutdown. # This value is recommended to be increased for installations with data dirs located in RAID array. #当Kafka启动时恢复数据和关闭时保存数据到磁盘时使用的线程个数。 num.recovery.threads.per.data.dir=2 ############################# Internal Topic Settings ############################# # The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state" # For anything other than development testing, a value greater than 1 is recommended for to ensure availability such as 3. #副本个数。除了开发测试外，其他情况都建议将该值设置为大于1的值以保证高可用，比如：3。 offsets.topic.replication.factor=2 transaction.state.log.replication.factor=2 transaction.state.log.min.isr=2 ############################# Log Flush Policy ############################# #Log持久化策略： #Message会立即写入到文件系统。但我们只使用了fsync()方法，该操作并不会立即执行OS的写入磁盘操作。 #下面几个参数可以配置写入磁盘的策略。 # Messages are immediately written to the filesystem but by default we only fsync() to sync # the OS cache lazily. The following configurations control the flush of data to disk. # There are a few important trade-offs here: # 1. Durability: Unflushed data may be lost if you are not using replication. # 2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush. # 3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to excessive seeks. # The settings below allow one to configure the flush policy to flush data after a period of time or # every N messages (or both). This can be done globally and overridden on a per-topic basis. # The number of messages to accept before forcing a flush of data to disk #在持久化到磁盘前message最大接收条数。 #log.flush.interval.messages=10000 # The maximum amount of time a message can sit in a log before we force a flush #持久化的最大时间间隔。 #log.flush.interval.ms=1000 ############################# Log Retention Policy ############################# #Log保留策略： #下面的参数配置如何处理log分片。可以配置为删除超过指定时间的数据，或超过指定大小的数据。 #如果一个segment符合其中任意调节，就会被删除。 # The following configurations control the disposal of log segments. The policy can # be set to delete segments after a period of time, or after a given size has accumulated. # A segment will be deleted whenever *either* of these criteria are met. Deletion always happens # from the end of the log. # The minimum age of a log file to be eligible for deletion due to age #将已保存超过7天的数据删除。 log.retention.hours=168 # A size-based retention policy for logs. Segments are pruned from the log unless the remaining # segments drop below log.retention.bytes. Functions independently of log.retention.hours. #基于数据大小的log保存策略。当分片的大小超过该值时，就会被删除。改功能不依赖于log.retention.hours。 #log.retention.bytes=1073741824 # The maximum size of a log segment file. When this size is reached a new log segment will be created. #单个分片的上限，达到该大小后会生成新的日志分片。 log.segment.bytes=1073741824 # The interval at which log segments are checked to see if they can be deleted according # to the retention policies #日志分片的检测时间间隔，每隔该事件会根据log保留策略决定是否删除log分片。 log.retention.check.interval.ms=300000 ############################# Zookeeper ############################# # Zookeeper connection string (see zookeeper docs for details). # This is a comma separated host:port pairs, each corresponding to a zk # server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002". # You can also append an optional chroot string to the urls to specify the # root directory for all kafka znodes. #Zookeeper连接字符串。是一个使用逗号分隔的host：port字符串。 zookeeper.connect=172.16.3.177:12181,172.16.3.178:12181,172.16.3.179:12181 # Timeout in ms for connecting to zookeeper #连接zookeeper的超时时间。 zookeeper.connection.timeout.ms=6000 ############################# Group Coordinator Settings ############################# #消费者分组协调者设置： # The following configuration specifies the time, in milliseconds, that the GroupCoordinator will delay the initial consumer rebalance. # The rebalance will be further delayed by the value of group.initial.rebalance.delay.ms as new members join the group, up to a maximum of max.poll.interval.ms. # The default value for this is 3 seconds. # We override this to 0 here as it makes for a better out-of-the-box experience for development and testing. # However, in production environments the default value of 3 seconds is more suitable as this will help to avoid unnecessary, and potentially expensive, rebalances during application startup. #在开发测试环境下该值设置为0，保证启动后马上可以使用。但在生产环境下，默认值3秒更适合。 group.initial.rebalance.delay.ms=0
Kafka集群搭建
在每个服务器中下载一个kafka，然后修改配置文件：
broker.id=0 （编号，类似于zookeeper的myid）
listeners=PLAINTEXT://192.168.1.103:9092 （监听）
zookeeper.connect=192.168.1.110:2181 （zookeeper）
配置好了这三项，启动就可以了。