Master: 192.168.124.128 Slave: 192.168.124.129
配置主从复制最好关闭防火墙：
systemctl stop firewalld #关闭selinux（临时） setenforce 0 #永久关闭selinux vi /etc/selinux/config # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - No SELinux policy is loaded. SELINUX=enforcing #将 enforcing --> disabled # SELINUXTYPE= can take one of three values: # targeted - Targeted processes are protected, # minimum - Modification of targeted policy. Only selected processes are protected. # mls - Multi Level Security protection. SELINUXTYPE=targetedMaster端安装及配置 yum下载mysql：
yum install mariadb mariadb-server epel-release net-tools -y #配置阿里镜像源： wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo启动mysql并添加到开机自启：
#启动并设置开机自启 systemctl start mariadb && systemctl enable mariadb
查看mysql是否正常启动：
[root@master ~]# netstat -nltp;ps -ef|grep mysql Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1143/sshd tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 1533/mysqld tcp6 0 0 :::22 :::* LISTEN 1143/sshd mysql 1215 1 0 21:19 ? 00:00:00 /bin/sh /usr/bin/mysqld_safe --basedir=/usr mysql 1533 1215 0 21:19 ? 00:00:01 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --log-error=/var/log/mariadb/mariadb.log --pid-file=/var/run/mariadb/mariadb.pid --socket=/var/lib/mysql/mysql.sock root 2131 1466 0编辑/etc/my.cnf文件
在[mysqld]下添加配置：
server-id=1 #数据库唯一ID，主从的标识号绝对不能重复,master端server-id与slave端不一样即可，相当于身份id log-bin=mysql-bin #开启bin-log，并指定文件目录和文件名前缀，记录执行的sql语句，相当于日志功能 binlog-ignore-db=mysql #不同步的系统数据库。如果是多个不同步库，就以此格式另写几行；也可以在一行，中间逗号隔开 sync_binlog = 1 #确保binlog日志写入后与硬盘同步 binlog_checksum = none #跳过现有的采用checksum的事件，mysql5.6.5以后的版本中binlog_checksum=crc32,而低版本都是binlog_checksum=none binlog_format = mixed #bin-log日志文件格式，设置为MIXED可以防止主键重复配置文件修改完成后重启mysql
systemctl restart mariadb在master上设置同步权限：
#先进入数据库：
@master ~]# mysql
#设置数据库密码
set password for root@localhost = password('new passwd');
# 只允许192.168.124.129使用root用户，且密码为"123"连接主库做数据同步
grant replication slave,replication client on *.* to root@'192.168.124.129' identified by "123";
#允许所有使用root用户,密码为"123"连接主库做数据同步
grant replication slave,replication client on *.* to root@'%' identified by "123";
# 刷新权限
flush privileges;
# 权限查看
show grants;
show grants for root@'192.168.128.129';
锁库(防止导出过程中有数据写入)
#锁定数据库 flush tables with read lock; #查看数据库状态： show master status； #创建目录 mkdir /dump #导出需要同步的库 mysqldump -uroot -p'' -S /var/lib/mysql/mysql.sock --events -A -B |gzip >/dump/mysql_back.$(date +%F).sql.gz Enter password: 输入数据库密码 # 解除锁定 unlock tables;slave端安装及配置：
安装跟master一样（建议不要克隆）
编辑/etc/my.cnf
在[mysqld]下面添加：
server-id=2 #设置从服务器id，必须于主服务器不同 replicate-ignore-db=mysql #不同步的数据库 slave-skip-errors = all #跳过所有的错误，继续执行复制操作
配置完重启mysql
systemctl restart mariadb把从主库导出的数据恢复到从库
@master ~]# cd /dump @master dump]# scp mysql_back.2022-06-06.sql.gz root@192.168.124.129:/dump配置主从同步指令
#进入Slave数据库 mysql ＃执行同步前，要先关闭slave stop slave; #在master库查看 MariaDB [(none)]> show master status; +------------------+----------+--------------+------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+----------+--------------+------------------+ | mysql-bin.000002 | 245 | | mysql | +------------------+----------+--------------+------------------+ #需要和主数据库的show master status命令结果保持一致 change master to master_host='192.168.124.128',master_user='root',master_password='123',master_log_file='mysql-bin.000002',master_log_pos=245; #启动Slave端 start slave; #查询数据库状态： show slave status G; #有以下三个就说明配置成功了 Slave_IO_Running: Yes Slave_SQL_Running: Yes Seconds_Behind_Master: 0在Master写入数据查看是否同步
主库创建数据库
