Install and configure a Kafka cluster with ZooKeeper to play with it.
Update package index.
$ sudo apt update
Install GNU privacy guard.
$ sudo apt -y install gpg
Install Java.
$ sudo apt -y install openjdk-11-jre-headless
Create a dedicated kafka user.
$ sudo adduser --system --home /opt/kafka --shell /bin/bash --uid 809 --group --disabled-login kafka
Create a download directory.
$ sudo -u kafka mkdir /opt/kafka/software
Download software and its ASCII-armored signature.
$ sudo -u kafka wget --quiet --directory-prefix /opt/kafka/software https://downloads.apache.org/kafka/2.8.0/kafka_2.13-2.8.0.tgz
$ sudo -u kafka wget --quiet --directory-prefix /opt/kafka/software https://downloads.apache.org/kafka/2.8.0/kafka_2.13-2.8.0.tgz.asc
Download the public key used to sign this archive.
$ gpg --keyserver keyserver.ubuntu.com --recv-key 87101C7E5C6DB1C98ADBF93B016CCFCA0E2FD561
Verify signature.
$ gpg --verify /opt/kafka/software/kafka_2.13-2.8.0.tgz.asc /opt/kafka/software/kafka_2.13-2.8.0.tgz
gpg: Signature made Wed Apr 14 14:37:43 2021 UTC gpg: using RSA key 87101C7E5C6DB1C98ADBF93B016CCFCA0E2FD561 gpg: issuer "vvcephei@apache.org" gpg: Good signature from "John Roesler (CODE SIGNING KEY) <vvcephei@apache.org>" [unknown] gpg: WARNING: This key is not certified with a trusted signature! gpg: There is no indication that the signature belongs to the owner. Primary key fingerprint: 8710 1C7E 5C6D B1C9 8ADB F93B 016C CFCA 0E2F D56
Create an application directory.
$ sudo -u kafka mkdir /opt/kafka/kafka
Extract application.
$ sudo -u kafka tar --directory /opt/kafka/kafka --strip-components 1 --extract --file /opt/kafka/software/kafka_2.13-2.8.0.tgz
Create Kafka data directory.
$ sudo -u kafka mkdir /opt/kafka/kafka/kafka_data
Create ZooKeeper data directory.
$ sudo -u kafka mkdir /opt/kafka/kafka/zookeeper_data
Update ZooKeeper myid file.
$ hostname -s | sed "s/.*\([^0-9]\)//g" | sudo -u kafka tee /opt/kafka/kafka/zookeeper_data/myid
Create ZooKeeper configuration.
$ sudo -u kafka cat <<EOF | tee /opt/kafka/kafka/config/zookeeper.properties tickTime=2000 initLimit=10 syncLimit=5 dataDir=/opt/kafka/kafka/zookeeper_data clientPort=2181 server.1=kafka1.example.org:2888:3888 server.2=kafka2.example.org:2888:3888 server.3=kafka3.example.org:2888:3888 EOF
Create Kafka configuration.
$ sudo -u kafka cat <<EOF | tee /opt/kafka/kafka/config/server.properties
# Licensed to the Apache Software Foundation (ASF) under one or more [83/1881]
# 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.id=$(hostname -s | sed "s/.*\([^0-9]\)//g")
############################# 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=PLAINTEXT://: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().
advertised.listeners=PLAINTEXT://$(hostname -f):9092
# Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details
#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
num.network.threads=3
# The number of threads that the server uses for processing requests, which may include disk I/O
num.io.threads=8
# The send buffer (SO_SNDBUF) used by the socket server
socket.send.buffer.bytes=102400
# The receive buffer (SO_RCVBUF) used by the socket server
socket.receive.buffer.bytes=102400
# The maximum size of a request that the socket server will accept (protection against OOM)
socket.request.max.bytes=104857600
############################# Log Basics #############################
# A comma separated list of directories under which to store log files
log.dirs=/opt/kafka/kafka/kafka_data
# 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.
num.partitions=6
# 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.
num.recovery.threads.per.data.dir=1
############################# 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 to ensure availability such as 3.
offsets.topic.replication.factor=1
transaction.state.log.replication.factor=1
transaction.state.log.min.isr=1
############################# Log Flush Policy #############################
# 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
#log.flush.interval.messages=10000
# The maximum amount of time a message can sit in a log before we force a flush
#log.flush.interval.ms=1000
############################# Log Retention Policy #############################
# 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
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.
#log.retention.bytes=1073741824
# The maximum size of a log segment file. When this size is reached a new log segment will be created.
log.segment.bytes=1073741824
# The interval at which log segments are checked to see if they can be deleted according
# to the retention policies
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.connect=localhost:2181
# Timeout in ms for connecting to zookeeper
zookeeper.connection.timeout.ms=18000
############################# Group Coordinator Settings #############################
# 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.
group.initial.rebalance.delay.ms=0
EOF
Create Zookeeper service.
$ cat <<EOF | sudo tee /etc/systemd/system/zookeeper.service [Unit] Description=ZooKeeper Service After=network-online.target Requires=network-online.target [Service] Type=simple Restart=on-failure User=kafka Group=kafka ExecStart=/opt/kafka/kafka/bin/zookeeper-server-start.sh /opt/kafka/kafka/config/zookeeper.properties ExecStop=/opt/kafka/kafka/bin/zookeeper-server-stop.sh /opt/kafka/kafka/config/zookeeper.properties WorkingDirectory=/opt/kafka [Install] WantedBy=multi-user.target EOF
Create Kafka service.
$ cat <<EOF | sudo tee /etc/systemd/system/kafka.service [Unit] Description=kafka Service After=network-online.target Requires=network-online.target [Service] Type=simple Restart=on-failure User=kafka Group=kafka ExecStart=/opt/kafka/kafka/bin/kafka-server-start.sh /opt/kafka/kafka/config/server.properties ExecStop=/opt/kafka/kafka/bin/kafka-server-stop.sh /opt/kafka/kafka/config/server.properties WorkingDirectory=/opt/kafka [Install] WantedBy=multi-user.target EOF
Reload systemd configuration.
$ sudo systemctl daemon-reload
Start ZooKeeper.
$ sudo systemctl start zookeeper
Start Kafka.
$ sudo systemctl start kafka