Centos builds a zookeeper high-availability cluster

zookeeper-ha

Host name	IP address
spark01	192.168.171.101
spark02	192.168.171.102
spark03	192.168.171.103

1. Upgrade kernel and software

yum -y update

2. Install commonly used software

yum -y install gcc gcc-c + + autoconf automake cmake make \
 zlib zlib-devel openssl openssl-devel pcre-devel \
 rsync openssh-server vim man zip unzip net-tools tcpdump lrzsz tar wget

3. Turn off the firewall

sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
setenforce 0
systemctl stop firewalld
systemctl disable firewalld

4. Modify host name

hostnamectl set-hostname spark01

hostnamectl set-hostname spark02

hostnamectl set-hostname spark03

5. Modify IP address

vim /etc/sysconfig/network-scripts/ifcfg-ens32

Reference is as follows:

TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="none"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens32"
DEVICE="ens32"
ONBOOT="yes"
IPADDR="192.168.171.101"
PREFIX="24"
GATEWAY="192.168.171.2"
DNS1="192.168.171.2"
IPV6_PRIVACY="no"

6. Modify hosts configuration file

vim /etc/hosts

The modifications are as follows:

192.168.171.101 spark01
192.168.171.102 spark02
192.168.171.103 spark03

7. Restart the system

reboot

8. Download and install JDK and Zookeeper and configure environment variables

Create software directories on all host nodes

mkdir -p /opt/soft

The following operations are completed on the spark01 host

Enter the software directory

cd /opt/soft

Download JDK

wget https://download.oracle.com/otn/java/jdk/8u391-b13/b291ca3e0c8548b5a51d5a5f50063037/jdk-8u391-linux-x64.tar.gz?AuthParam=1698206552_11c0bb831efdf87adfd187b 0e4ccf970

Download ZooKeeper

wget https://dlcdn.apache.org/zookeeper/zookeeper-3.8.3/apache-zookeeper-3.8.3-bin.tar.gz

Unzip JDK and change the name

Unzip zookeeper and change the name

tar -zxvf jdk-8u391-linux-x64.tar.gz
mv jdk1.8.0_391 jdk-8
tar -zxvf apache-zookeeper-3.8.3-bin.tar.gz
mv apache-zookeeper-3.8.3-bin zookeeper-3

Configure environment variables

vim /etc/profile.d/my_env.sh

Write the following:

export JAVA_HOME=/opt/soft/jdk-8
export set JAVA_OPTS="--add-opens java.base/java.lang=ALL-UNNAMED"

export ZOOKEEPER_HOME=/opt/soft/zookeeper-3

export PATH=$PATH:$JAVA_HOME/bin:$ZOOKEEPER_HOME/bin

Make environment variables effective on each server

source /etc/profile

10. Edit configuration file

cd $ZOOKEEPER_HOME/conf

vim zoo.cfg

# Heartbeat unit, 2s
tickTime=2000
# Zookeeper-3 initialization synchronization timeout, 10 heartbeat units, that is, 20s
initLimit=10
# Ordinary synchronization: timeout for sending a request and getting a response, 5 heartbeat units, which is 10s
syncLimit=5
# Storage location of memory snapshot data
dataDir=/home/zookeeper-3/data
#Transaction log storage location
dataLogDir=/home/zookeeper-3/datalog
# Port of the current zookeeper-3 node
clientPort=2181
# The number of concurrent connections from a single client to a single node in the cluster. Determine whether it is the same client through IP. The default is 60
maxClientCnxns=1000
# Keep 7 memory snapshot files in dataDir, 3 by default
autopurge.snapRetainCount=7
# Clear the scheduled task of the snapshot, the default is 1 hour, if set to 0, it indicates that the clearing task is closed
autopurge.purgeInterval=1
#The minimum timeout allowed for client connection settings, the default is 2 heartbeat units
minSessionTimeout=4000
#The maximum timeout time allowed for client connection settings. The default is 20 heartbeat units, which is 40s.
maxSessionTimeout=300000
#zookeeper-3 3.5.5 will start the AdminService service by default. This service defaults to port 8080.
admin.serverPort=9001
#Cluster address configuration
server.1=spark01:2888:3888
server.2=spark02:2888:3888
server.3=spark03:2888:3888

tickTime=2000
initLimit=10
syncLimit=5
dataDir=/home/zookeeper-3/data
dataLogDir=/home/zookeeper-3/datalog
clientPort=2181
maxClientCnxns=1000
autopurge.snapRetainCount=7
autopurge.purgeInterval=1
minSessionTimeout=4000
maxSessionTimeout=300000
admin.serverPort=9001
server.1=spark01:2888:3888
server.2=spark02:2888:3888
server.3=spark03:2888:3888

11. Create a directory based on the configuration file after saving

Execute on each server

mkdir -p /home/zookeeper-3/data
mkdir -p /home/zookeeper-3/datalog

12. Write zookeeper-3 startup script

Create a startup script zookeeper-3.service in the /etc/systemd/system/ folder

NOTE: Write on each server

cd /etc/systemd/system
vim zookeeper.service

The content is as follows:

[Unit]
Description=zookeeper
After=syslog.target network.target

[Service]
Type=forking
# Specify the zookeeper-3 log file path, which can also be defined in zkServer.sh
Environment=ZOO_LOG_DIR=/home/zookeeper-3/datalog
# Specify the JDK path, which can also be defined in zkServer.sh
Environment=JAVA_HOME=/opt/soft/jdk-8
ExecStart=/opt/soft/zookeeper-3/bin/zkServer.sh start
ExecStop=/opt/soft/zookeeper-3/bin/zkServer.sh stop
Restart=always
User=root
Group=root

[Install]
WantedBy=multi-user.target

[Unit]
Description=zookeeper
After=syslog.target network.target

[Service]
Type=forking
Environment=ZOO_LOG_DIR=/home/zookeeper-3/datalog
Environment=JAVA_HOME=/opt/soft/jdk-8
ExecStart=/opt/soft/zookeeper-3/bin/zkServer.sh start
ExecStop=/opt/soft/zookeeper-3/bin/zkServer.sh stop
Restart=always
User=root
Group=root

[Install]
WantedBy=multi-user.target

systemctl daemon-reload
# Wait until all hosts are configured before executing the following command
systemctl start zookeeper
systemctl enable zookeeper
systemctl status zookeeper

13. Configure ssh key-free login

Create a local key and write the public key to the authentication file

ssh-keygen -t rsa -P '' -f ~/.ssh/id_rsa

ssh-copy-id root@spark01

ssh-copy-id root@spark02

ssh-copy-id root@spark03

ssh root@spark01
exit

ssh root@spark02
exit

ssh root@spark03
exit

14. Distributing software and configuration files

Distribute ssh keyless

scp -r ~/.ssh root@spark02:~/
scp -r ~/.ssh root@spark03:~/

Distribute hosts file

scp -r /etc/hosts root@spark02:/etc/
scp -r /etc/hosts root@spark03:/etc/

Distribute software

scp -r /opt/soft/jdk-8 root@spark02:/opt/soft
scp -r /opt/soft/zookeeper-3 root@spark02:/opt/soft
scp -r /opt/soft/jdk-8 root@spark03:/opt/soft
scp -r /opt/soft/zookeeper-3 root@spark03:/opt/soft

Distribute environment variables

scp /etc/profile.d/my_env.sh root@spark02:/etc/profile.d/
scp /etc/profile.d/my_env.sh root@spark03:/etc/profile.d/

Make the new environment variables take effect on all host nodes

source /etc/profile

15.myid

spark01

echo 1 >/home/zookeeper-3/data/myid
more /home/zookeeper-3/data/myid

spark02

echo 2 > /home/zookeeper-3/data/myid
more /home/zookeeper-3/data/myid

spark03

echo 3 > /home/zookeeper-3/data/myid
more /home/zookeeper-3/data/myid

16. Start service

Execute the following commands on each node

systemctl daemon-reload
systemctl start zookeeper
systemctl enable zookeeper
systemctl status zookeeper

17. Verification

jps

zkServer.sh status