目录
1、master开启二进制日志记录
2、slave开启IO进程，从master中读取二进制日志并写入slave的中继日志
3、slave开启SQL进程，从中继日志中读取二进制日志并进行重放
4、最终，达到slave与master中数据一致的状态，我们称作为主从复制的过程。
基础环境设置
网络对时
主与从主机都需要操作
[root@localhost ~]# cat /etc/chrony.conf | grep -Ev '^$|#'
server ntp.aliyun.com iburst
driftfile /var/lib/chrony/drift
makestep 1.0 3
rtcsync
keyfile /etc/chrony.keys
leapsectz right/UTC
logdir /var/log/chrony
[root@slave1 ~]# timedatectl set-timezone Asia/Shanghai
[root@slave1 ~]# systemctl restart chronyd.service 防火墙与SELinux
[root@localhost ~]# systemctl disable --now firewalld
[root@localhost ~]# sed -i 's/SELIUNX=enforcing/SELINUX=disable/' /etc/selinux/config
[root@localhost ~]# setenforce 0配置主从复制
配置master配置文件
[root@localhost ~]# cd /etc/my.cnf.d/
[root@localhost my.cnf.d]# ls
mysql-server.cnf
[root@localhost my.cnf.d]# vi mysql-server.cnf
#
# This group are read by MySQL server.
# Use it for options that only the server (but not clients) should see
#
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/en/server-configuration-defaults.html
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mysqld according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-error=/var/log/mysql/mysqld.log
pid-file=/run/mysqld/mysqld.pid
log-bin=mysql-bin
binlog_format="statement"
server-id=11
log-slave-updates=true启动服务
[root@localhost my.cnf.d]# systemctl enable --now mysqld
Created symlink /etc/systemd/system/multi-user.target.wants/mysqld.service → /usr/lib/systemd/system/mysqld.service.创建一个可以在从主机访问的账户并查看正在使用的日志文件及日志书写位置
[root@localhost my.cnf.d]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.42 Source distribution
Copyright (c) 2000, 2025, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> create user slave@'192.168.44.%' identified by '123.com';
Query OK, 0 rows affected (0.00 sec)
mysql> grant all on *.* to 'slave'@'192.168.44.%';
Query OK, 0 rows affected (0.00 sec)
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000002 | 713 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)注意：查看位置完毕后，不要对master做insert、update、delete、create、drop等操作！！！
从服务器配置
[root@localhost ~]# vi /etc/my.cnf.d/mysql-server.cnf
#
# This group are read by MySQL server.
# Use it for options that only the server (but not clients) should see
#
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/en/server-configuration-defaults.html
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mysqld according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-error=/var/log/mysql/mysqld.log
pid-file=/run/mysqld/mysqld.pid
log-bin=mysql-bin
binlog_format="statement"
relay-log-index=slave-bin.index
server-id=22此时没有与主服务器进行连接，所以没有产生对应的relay log
systemctl enable --now mysqld
Created symlink /etc/systemd/system/multi-user.target.wants/mysqld.service → /usr/lib/systemd/system/mysqld.service.
[root@localhost ~]# cd /var/lib/mysql
[root@localhost mysql]# ls
auto.cnf ibdata1 mysql.ibd public_key.pem
ca-key.pem ibtmp1 mysql.sock server-cert.pem
ca.pem '#innodb_redo' mysql.sock.lock server-key.pem
client-cert.pem '#innodb_temp' mysql_upgrade_info sys
client-key.pem mysql mysqlx.sock undo_001
'#ib_16384_0.dblwr' mysql-bin.000001 mysqlx.sock.lock undo_002
'#ib_16384_1.dblwr' mysql-bin.000002 performance_schema
ib_buffer_pool mysql-bin.index private_key.pem
配置从服务器的所属主服务器
[root@localhost mysql]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.42 Source distribution
Copyright (c) 2000, 2025, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> change master to master_host='192.168.44.163',master_user='slave',master_pas
sw
Query OK, 0 rows affected, 8 warnings (0.01 sec)
mysql> start slave
-> ;
Query OK, 0 rows affected, 1 warning (0.03 sec)
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Connecting to source
Master_Host: 192.168.44.163
Master_User: slave
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 713
Relay_Log_File: localhost-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: mysql-bin.000002
Slave_IO_Running: yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 713
Relay_Log_Space: 157
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 2061
Last_IO_Error: Error connecting to source 'slave@192.168.44.163:3306'. This was attempt 1/86400, with a delay of 60 seconds between attempts. Message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection.
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 0
Master_UUID:
Master_Info_File: mysql.slave_master_info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Replica has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp: 250717 09:32:17
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
Master_public_key_path:
Get_master_public_key: 0
Network_Namespace:
1 row in set, 1 warning (0.00 sec)
查看配置是否生效
[root@localhost ~]# cd /var/lib/mysql
[root@localhost mysql]# ls
auto.cnf ibtmp1 mysqlx.sock.lock
binlog.000001 '#innodb_redo' performance_schema
binlog.index '#innodb_temp' private_key.pem
ca-key.pem localhost-relay-bin.000001 public_key.pem
ca.pem localhost-relay-bin.000002 server-cert.pem
client-cert.pem mysql server-key.pem
client-key.pem mysql.ibd slave-bin.index
'#ib_16384_0.dblwr' mysql.sock sys
'#ib_16384_1.dblwr' mysql.sock.lock undo_001
ib_buffer_pool mysql_upgrade_info undo_002
ibdata1 mysqlx.sock主服务器建立一个数据库能同步到从主机
mysql> create database test;
Query OK, 1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
+--------------------+
5 rows in set (0.01 sec)