Step-by-Step Guide to Install and Upgrade Zabbix 4.0 → 4.2 on CentOS 7

1. Add Zabbix Repository

1. Install repository package

rpm -ivh https://repo.zabbix.com/zabbix/4.2/rhel/7/x86_64/zabbix-release-4.2-1.el7.noarch.rpm

2. Enable optional RPMs

yum-config-manager --enable rhel-7-server-optional-rpms

3. Install Zabbix server with MySQL support

yum install zabbix-server-mysql

4. Install Zabbix web frontend with MySQL support

yum install zabbix-web-mysql

2. Install MySQL 5.7

1. Remove existing MariaDB packages

rpm -qa | grep mariadb
rpm -e --nodeps mariadb-libs-5.5.52-1.el7.x86_64

2. Download and extract MySQL source

wget https://dev.mysql.com/get/archives/mysql-5.7/mysql-5.7.21-linux-glibc2.12-x86_64.tar.gz
tar -xzvf mysql-5.7.21-linux-glibc2.12-x86_64.tar.gz
mv mysql-5.7.21-linux-glibc2.12-x86_64 /usr/local/mysql

3. Create MySQL user and group, set ownership

groupadd mysql
useradd -r -g mysql mysql
chown -R mysql.mysql mysql/

4. Create MySQL configuration file

cat >>/etc/my.cnf <<EOF
[client]
port = 3306
socket = /tmp/mysql.sock
[mysqld]
character_set_server=utf8
init_connect='SET NAMES utf8'
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
socket=/tmp/mysql.sock
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
lower_case_table_names = 1
sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
max_connections=5000
default-time_zone = '+8:00'
EOF

5. Initialize the database

touch /var/log/mysqld.log
chmod 777 /var/log/mysqld.log
chown mysql.mysql mysqld.log
/usr/local/mysql/bin/mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data

6. Retrieve the temporary root password

cat /var/log/mysqld.log | grep root@localhost

7. Start MySQL service and set permissions

mkdir /var/run/mysqld
touch /var/run/mysqld/mysqld.pid
chmod -R 777 /var/run/mysqld
chown -R mysql.mysql /var/run/mysqld
/usr/local/mysql/support-files/mysql.server start

8. Change the MySQL root password

vim /etc/my.cnf   # add skip-grant-tables, default_password_lifetime=360
/usr/local/mysql/bin/mysql -uroot -p   # login
use mysql;
update mysql.user set authentication_string = password('root'), host = '%' where user = 'root';
flush privileges;

9. Add MySQL to system PATH

echo 'PATH=/usr/local/mysql/bin:$PATH' >>/etc/profile
ln -s /usr/local/mysql/support-files/mysql.server /usr/local/mysql/bin/

10. Create Zabbix database and user

mysql> create database zabbix character set utf8 collate utf8_bin;
mysql> grant all privileges on zabbix.* to zabbix@localhost identified by 'zabbix';
mysql> flush privileges;

11. Configure Zabbix server

vim /etc/zabbix/zabbix_server.conf
DBName=zabbix
DBHost=192.168.179.132
DBUser=zabbix
DBPassword=zabbix

Create PID file

touch /var/run/zabbix/zabbix_server.pid
chmod 777 /var/run/zabbix/zabbix_server.pid

Start Zabbix server

systemctl enable zabbix-server
systemctl start zabbix-server

12. Import initial data

zcat /usr/share/doc/zabbix-server-mysql*/create.sql.gz | mysql -uzabbix -p zabbix

3. Install Nginx

1. Disable firewall and SELinux

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

2. Install dependencies

yum -y install wget vim lsof lrzsz pcre-devel zlib-devel make gd-devel libjpeg-devel libpng-devel libxml2-devel bzip2-devel libcurl-devel libmcrypt libmcrypt-devel mcrypt mhash net-snmp-devel gcc bison bison-devel openssl-devel readline-devel libedit-devel sqlite-devel freetype freetype-devel libevent-devel mysql-devel

3. Configure Nginx repository

cat >>/etc/yum.repos.d/nginx.repo <<EOF
[nginx]
name=nginx.repo
baseurl=http://nginx.org/packages/centos/7/$basearch/
gpgcheck=0
enabled=1
skip_if_unavailable = 1
keepcache = 0
EOF

4. Install and start Nginx

yum install nginx -y
systemctl start nginx
systemctl enable nginx

4. Install PHP

1. Add PHP user

useradd -s /sbin/nologin php-fpm

2. Install PHP dependencies

yum install -y gcc gcc-c++ make zlib zlib-devel pcre pcre-devel libjpeg libjpeg-devel libpng libpng-devel freetype freetype-devel libxml2 libxml2-devel glibc glibc-devel glib2 glib2-devel bzip2 bzip2-devel ncurses ncurses-devel curl curl-devel e2fsprogs e2fsprogs-devel krb5 krb5-devel openssl openssl-devel openldap openldap-devel nss_ldap openldap-clients openldap-servers

3. Compile and install PHP 7.2.6

wget http://mirrors.sohu.com/php/php-7.2.6.tar.gz
tar zxvf php-7.2.6.tar.gz
cd php-7.2.6
./configure --prefix=/usr/local/php --with-config-file-path=/usr/local/php/etc --enable-fpm --with-fpm-user=php-fpm --with-fpm-group=php-fpm --with-mysql=mysqlnd --with-pdo-mysql=mysqlnd --with-mysqli=mysqlnd --with-libxml-dir --with-gd --with-jpeg-dir --with-png-dir --with-freetype-dir --with-iconv-dir --with-zlib-dir --with-mcrypt --enable-soap --enable-gd-native-ttf --enable-ftp --enable-mbstring --enable-exif --disable-ipv6 --with-pear --with-curl --enable-bcmath --enable-mbstring --enable-sockets --with-gd --with-libxml-dir=/usr/local --with-gettext
make && make install
cp php.ini-production /usr/local/php/etc/php.ini

4. Adjust PHP configuration

sed -i 's/post_max_size = 8M/post_max_size = 32M/g' /usr/local/php/etc/php.ini
sed -i 's/upload_max_filesize = 2M/upload_max_filesize = 50M/g' /usr/local/php/etc/php.ini
sed -i 's/;date.timezone =/date.timezone =PRC/' /usr/local/php/etc/php.ini
sed -i 's/max_execution_time = 30/max_execution_time = 600/g' /usr/local/php/etc/php.ini
sed -i 's/max_input_time = 60/max_input_time = 600/g' /usr/local/php/etc/php.ini
sed -i 's/memory_limit = 128M/memory_limit = 256M/g' /usr/local/php/etc/php.ini
sed -i 's/; max_input_vars = 1000/max_input_vars = 10000/g' /usr/local/php/etc/php.ini

5. Start php-fpm

cp /usr/local/php/etc/php-fpm.conf.default /usr/local/php/etc/php-fpm.conf
cp /usr/local/php/etc/php-fpm.d/www.conf.default /usr/local/php/etc/php-fpm.d/www.conf
/usr/local/php/sbin/php-fpm -c /usr/local/php/etc/php.ini -y /usr/local/php/etc/php-fpm.conf

5. Install Zabbix Agent

yum install zabbix-agent
vim /etc/zabbix/zabbix-agentd.conf

Server and ServerActive fields should contain the Zabbix server IP; the last line enables script‑based data collection.

6. Install Zabbix Web Interface

1. Copy Zabbix PHP files to web root

cp -r /usr/share/zabbix/.* /usr/share/nginx/html/

2. Configure Nginx for Zabbix

egrep -v '(^.*#|^$)' /etc/nginx/conf.d/default.conf
server {
    listen       80;
    server_name  192.168.179.133;
    access_log  /var/log/nginx/host.access.log  main;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm index.php;
    }
    location /zabbix {
        root    /usr/share/nginx/html;
        index    index.html index.htm index.php;
    }
    error_page  404              /404.html;
    error_page   500 502 503 504  /50x.html;
    location = /50x.html { root   /usr/share/nginx/html; }
    location ~ \.php$ {
        root           html;
        fastcgi_pass   127.0.0.1:9000;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME  /usr/share/nginx/html$fastcgi_script_name;
        include        fastcgi_params;
    }
}

3. Set permissions and restart Nginx

chmod -R 777 /etc/zabbix/web.
chmod -R 777 /usr/share/nginx/html/zabbix
systemctl restart nginx

4. Access the web installer

Open a browser and navigate to http://192.168.179.133/zabbix to complete the Zabbix web setup.

7. Upgrade Zabbix from 4.0 to 4.2

1. Stop Zabbix server (and proxy if present)

systemctl stop zabbix-server

2. Backup existing Zabbix 4.0 data

mysqldump -uzabbix -p --single-transaction --master-data=2 --databases zabbix > olddata.sql

3. Update repository package

rpm -Uvh https://repo.zabbix.com/zabbix/4.2/rhel/7/x86_64/zabbix-release-4.2-1.el7.noarch.rpm

4. Upgrade Zabbix components

yum upgrade zabbix-server-mysql zabbix-web-mysql zabbix-agent

5. Start Zabbix server

systemctl start zabbix-server

6. Adjust web permissions

chmod 777 -R /etc/zabbix/web

7. Copy frontend files to web directory

cp -r /usr/share/zabbix/.* /usr/share/nginx/html/

Upgrade to Zabbix 4.2 is now complete.

Feel free to discuss further improvements.