mysql安装版本及下载地址：https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz
检查系统中的Mysql和mariadb，如果存在将其卸载
#rpm -qa | grep mysql
#rpm -qa | grep mariadb
#mariadb-libs-5.5.65-1.el7.x86_64
#yum -y remove mariadb-libs-5.5.65-1.el7.x86_64创建mysql用户组和mysql用户
# groupadd mysql
#useradd -g mysql -s /sbin/nologin mysql解压安装包
#tar -zxvf mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
# cd /usr/local/
# mv mysql-5.7.26-linux-glibc2.12-x86_64 mysql设置mysql环境变量
#vi /etc/profile.d/mysql.sh
export PATH=/usr/local/mysql/bin:$PATH
# source /etc/profile.d/mysql.sh配置mysql
#mkdir -pv /data/mysql
#chown mysql.mysql /data/mysql
# chmod go-rwx /data/mysql初始化数据库并注意日志里面输出的默认密码
#yum install -y libaio
#mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/data/mysql
配置启动脚本
# cp /usr/local/mysql/support-files/mysql.server /etc/init.d/mysqld
# chkconfig --add mysqld
# chkconfig mysqld on
# chkconfig --list |grep mysqld编辑mysql配置文件/etc/my.cnf
[client]
port = 3306
socket = /tmp/mysql.sock
[mysqld]
port = 3306
socket = /tmp/mysql.sock
pid_file = /data/mysql/mysql.pid
datadir = /data/mysql
default_storage_engine = InnoDB
max_allowed_packet = 512M
max_connections = 2048
open_files_limit = 65535
skip-name-resolve
lower_case_table_names=1
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
init_connect='SET NAMES utf8mb4'
innodb_buffer_pool_size = 512M
innodb_log_file_size = 1024M
innodb_file_per_table = 1
innodb_flush_log_at_trx_commit = 0
key_buffer_size = 64M
log-error = /data/mysql/mysql_error.log
log-bin = /data/mysql/mysql-bin
binlog_format = mixed
expire_logs_days = 10
slow_query_log = 1
slow_query_log_file = /data/mysql/slow_query.log
long_query_time = 1
server-id=1启动mysql
vi /etc/init.d/mysqld
basedir=/usr/local/mysql //在第46行
datadir=/data/mysql
# /etc/init.d/mysqld start
Starting MySQL.Logging to '/data/mysql/localhost.localdomain.err'.
SUCCESS!
# mysql -uroot -p
mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.#这里错误提示你需要更改默认密码
mysql> alter user 'root'@'localhost' identified by '123456';
Query OK, 0 rows affected (0.00 sec)常见错误排除：
若出现无法登陆数据库可以在/etc/my.cnf最后一行加入skip-grant-tables，重启mysql后直接mysql登陆数据库，
mysql> use mysql；
mysql> update MySQL.user set authentication_string=password('root') where user='root' ;
mysql> flush privileges;更新数据库密码后删除掉my.cnf最后一行的skip-grant-tables，重启数据库验证新密码是否有效
两台数据库同样方式进行安装，安装完成开始进行主从同步的配置
master：192.168.100.10
slave：192.168.100.20
注意：从数据库服务器上一定要有主数据库服务器上的库、表且表结构要一致。
配置master数据库服务器
#ls -lrt /data/mysql
total 2121876
-rw-r----- 1 mysql mysql 56 May 23 16:06 auto.cnf
drwxr-x--- 2 mysql mysql 8192 May 23 16:06 performance_schema
drwxr-x--- 2 mysql mysql 4096 May 23 16:06 mysql
drwxr-x--- 2 mysql mysql 8192 May 23 16:06 sys
-rw-r----- 1 mysql mysql 29924 May 23 16:40 localhost.localdomain.err
-rw-r----- 1 mysql mysql 1073741824 May 23 16:41 ib_logfile1
-rw-r----- 1 mysql mysql 329 May 23 16:43 mysql-bin.000001
-rw-r----- 1 mysql mysql 718 May 23 16:46 mysql-bin.000002
-rw-r----- 1 mysql mysql 872 May 23 17:25 mysql-bin.000003
-rw-r----- 1 mysql mysql 177 May 23 17:43 mysql-bin.000004
drwxr-x--- 2 mysql mysql 52 May 23 17:54 zs
-rw-r----- 1 mysql mysql 666 May 23 18:00 mysql-bin.000005
-rw-r----- 1 mysql mysql 300 May 23 18:00 ib_buffer_pool
-rw-r----- 1 mysql mysql 1104 May 23 18:00 slow_query.log
-rw-r----- 1 mysql mysql 174 May 23 18:00 mysql-bin.index
-rw-r----- 1 mysql mysql 5 May 23 18:00 localhost.localdomain.pid
-rw-r----- 1 mysql mysql 12582912 May 23 18:00 ibtmp1
-rw-r----- 1 mysql mysql 41881 May 23 18:05 mysql_error.log
-rw-r----- 1 mysql mysql 726 May 23 19:14 mysql-bin.000006
-rw-r----- 1 mysql mysql 12582912 May 23 19:15 ibdata1
-rw-r----- 1 mysql mysql 1073741824 May 23 19:15 ib_logfile0
#vi /etc/my.cnf
#log-bin=mysql-bin.000006
server_id=1 #主库为1 从库为2修改过my.cnf后重启数据库
登陆数据库执行下面的操作：
mysql> grant replication slave on . to root@"%" identified by "123456";
配置slave数据库服务器
#vim /etc/my.cnf
server_id=2
log-bin=slavelog #可开可不开重启数据库
管理员登陆
mysql> change master to
-> master_host="192.168.100.10",
-> master_user="root",
-> master_password="123456",
-> master_log_file="mysql-bin.000006", 主查询show master status;
-> master_log_pos=0;
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)
mysql> show slave status\G;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes #两个进程状态为yes
mysql>show slave status;
测试验证主从状态是否正常,mster库新建数据库和表，并往表中插入数据，查看从库是否新建了同样的数据库和表，并查看表中数据一致性；
主库进行以下操作：
mysql> create database shanghai;
Query OK, 1 row affected (0.03 sec)
mysql> use shanghai;
Database changed
mysql> create table user
-> (
-> id INT(11),
-> name VARCHAR(25),
-> deptId INT(11),
-> salary FLOAT
-> );
Query OK, 0 rows affected (0.07 sec)
mysql> insert into user (id,name) values(1,'alex');
Query OK, 1 row affected (0.01 sec)
mysql> select *from user;
+------+------+--------+--------+
| id | name | deptId | salary |
+------+------+--------+--------+
| 1 | alex | NULL | NULL |
+------+------+--------+--------+
1 row in set (0.00 sec)
从库查看是否创建了与主库同样的数据库，并查看数据一致性：mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| shanghai |
| sys |
+--------------------+
5 rows in set (0.00 sec)
mysql> use shanghai;
mysql> select * from user;
+------+------+--------+--------+
| id | name | deptId | salary |
+------+------+--------+--------+
| 1 | alex | NULL | NULL |
+------+------+--------+--------+
1 row in set (0.00 sec)
经验证，主库创建数据库并往库内插入数据后，从库会同步主库的所有操作，主从同步正常。
工作原理
slave_io_running:yes
连接主数据库服务器，并把主数据库服务器binlog日志里sql语句拷贝本机的relybinlog日志里。
slave_sql_running:yes
执行本机relybinlog日志里的sql语句，把数据写到数据库里
四、测试主从同步
在主服务器上建库建表删除数据，从服务器会跟着同步;
/var/lib/msyql/
master.info 记录连接主数据库服务器的信息
relay-log.info 记录中继binlog日志信息
localhost-relay-bin.000001
localhost-relay-bin.000002 中继binlog日志
localhost-relay-bin.index 保存已有中继binlog日志文件名
常用的其他选项
适用于master服务器
binlog-do-db=name 设置master对哪些库记日志
binlog-ignore-db=name 设置master对哪些库不记日志
log-slave-updates 记录从库更新，允许链式复制（A-B-C）
relay-log=dbsvr2-relay-bin 指定中继日志文件名
replicate-do-db=mysql 仅复制指定库，其他库将被忽略，此选项可设置多条(省略时复制所有库)
replicate-ignore-db=test 不复制哪些库，其他库将被忽略，ignore-db与go-db只需选用其中一种
report-host=dbsvr2 报告给master的主机名或ip地址
slave-net-timeout=60 出现网络中断时，重试超时（默认60秒）