--- title: "MySQL 主从复制" date: 2019-10-30T17:33:13+08:00 lastmod: 2020-04-18T23:40:00+08:00 tags: ["mysql", "master", "slave", "gtid", "replication", "同步"] categories: ["database"] --- # 环境 - mysql 主服务器，centos7.4，192.168.1.10，端口 10000 - mysql 从服务器，centos7.4，192.168.1.6 - 要复制的数据库有 data_db、conf_db # 在主服务器上创建用于备份的用户 replicator ```sql grant replication slave on *.* to 'replicator'@'192.168.1.6' identified by 'password'; flush privileges; ``` # 在主服务器上修改 my.cnf ``` # 建议与本机ip地址最后一位一致,与其他互备服务器均不一致 server-id = 10 read-only = 0 # 开启 binlog log-bin = /var/log/mysql-bin/master binlog-format = row #关注要复制的数据库，存在跨库问题 binlog-do-db = data-db binlog-do-db = conf-db #忽略的数据库，存在跨库问题 #binlog-ignore-db = #binlog 有效时间 expire-logs-days = #GTID 复制模式 #gtid-mode = ON #enforce-gtid-consistency=true #双主或多主互备时，会用到以下配置 #自增主键初始值，与其他互备服务器一致 #auto-increment-offset = #自增主键等差值，与其他互备服务器均不一致 #auto-increment-increment = ``` # 在主服务器上重启 mysql，获取 master 状态 ```sql -- 如果 mysql 是全新安装，则无须导出数据库初态，直接查看 binlog pos 即可 -- 锁定要导出的数据库表 flush tables with read lock; ``` # 导出数据库初态 ```bash #在主服务器的另一个终端中运行 mysqldump -uroot -p data_db > /tmp/data_db.sql mysqldump -uroot -p conf_db > /tmp/conf_db.sql #复制到从服务器上 scp /tmp/data_db.sql /tmp/conf_db.sql 192.168.1.6:/tmp/ ``` # 查看 binary 日志位置 ```sql show master status\G -- 记住输出里的如下类似两行（不记录也可以，这两个信息已经写入了导出的sql文件中） -- File: mysql-bin.000001 -- Position: 137103822 -- 解锁数据库表 unlock tables; ``` # 在从服务器上编辑 my.cnf ``` # 建议与本机ip地址最后一位一致,与其他互备服务器均不一致 server-id = 6 read-only = 1 # 如果该 slave 中也运行了 master，或者使用了 gtid 模式复制，则开启 binlog #log-bin = mysql-bin #binlog-format = row # 把 slave 操作也计入 binlog，用于链式同步 #log-slave-updates = ON # 指定要复制的数据库，存在跨库问题 #replicate-do-db = data_db #replicate-do-db = conf_db # 指定要复制的数据表，无跨库问题 replicate-do-table = db1.t1 replicate-wild-do-table = db1.% # 忽略的数据库，存在跨库问题 #replicate-ignore-db = # 忽略的数据表，无跨库问题 #replicate-ignore-table = db1.t1 #replicate-wild-ignore-table = db1.% # 中继日志 relay-log = /var/lib/mysql-bin/slave # 多线程复制 slave-parallel-type = logical-clock slave-parallel-workers = 4 # GTID 模式 #gtid-mode = ON #enforce-gtid-consistency=true # 双主或多主互备时，会用到以下配置 # 自增主键初始值，与其他互备服务器一致 #auto-increment-offset = # 自增主键等差值，与其他互备服务器均不一致 #auto-increment-increment = ``` # 在从服务器上重启 mysql，导入初态 ```sql -- 创建要导入的数据库 create database data_db default charset utf8mb4; create database conf_db default charset utf8mb4; ``` # 导入数据库 ```bash msyql -uroot -p data_db < /tmp/data_db.sql mysql -uroot -p conf_db < /tmp/conf_db.sql ``` # 开启同步 ```sql -- 基于 binlog 文件位置复制 change master to master_host = '192.168.1.10', master_port = 3306, master_user = 'replicator', master_password = 'password', master_log_file = 'mysql-bin.000001', master_log_pos = 137103822; flush privileges; -- 基于 gtid 复制 change master to master_host = '192.168.1.10', master_port = 3306, master_user = 'replicator', master_password = 'password', master_auto_position = 1; ``` # 启动 slave，查看 slave 状态 ```sql start slave; -- 在从服务器上查看 slave 状态 show slave status\G -- 如果看到 -- Slave_IO_Running: Yes -- Slave_SQL_Running: Yes -- 则表示 slave 开启成功！ ``` # MySQL8 gtid 互为主从配置 ``` [mysqld] # ---- 固定配置 ---- datadir = /var/lib/mysql socket = /var/lib/mysql/mysql.sock pid-file = /var/lib/mysql/mysql.pid log-timestamps = SYSTEM log-error = /var/log/mysql/error.log slow-query-log = TRUE slow-query-log-file = /var/log/mysql/slow.log default-authentication-plugin = mysql_native_password # ---- 动态配置 ---- mysqlx = OFF character-set-server = utf8mb4 default-storage-engine = innodb lower-case-table-names = 1 #skip-name-resolve = 1 #max-user-connections = 600 #innodb-buffer-pool-size = 8G #innodb-buffer-pool-instances = 8 # master # 确认不同节点该 id 唯一 server-id = 1 log-bin = /var/lib/mysql-bin/master binlog-format = ROW #binlog-do-db = db1 binlog-expire-logs-seconds = 172800 gtid-mode = ON enforce-gtid-consistency = TRUE # slave replicate-wild-ignore-table = information_schema.% replicate-wild-ignore-table = mysql.% replicate-wild-ignore-table = performance_schema.% replicate-wild-ignore-table = sys.% slave-parallel-workers = 2 log-slave-updates = FALSE relay-log = /var/lib/mysql-bin/slave relay-log-recovery = TRUE #read-only = ON ``` # MySQL8 gtid 多源复制从库配置 - 修改 my.cnf ``` [mysqld] # ---- 固定配置 ---- datadir = /data/mysql socket = /var/lib/mysql/mysql.sock pid-file = /var/lib/mysql/mysql.pid log-timestamps = SYSTEM log-error = /var/log/mysql/error.log slow-query-log-file = /var/log/mysql/slow.log slow-query-log = TRUE default-authentication-plugin = mysql_native_password # ---- 动态配置 ---- mysqlx = OFF character-set-server = utf8mb4 default-storage-engine = innodb lower-case-table-names = 1 #skip-name-resolve = 1 #max-user-connections = 600 #innodb-buffer-pool-size = 8G #innodb-buffer-pool-instances = 8 # master server-id = 39 log-bin = /var/lib/mysql/master binlog-format = ROW #binlog-do-db = db1 gtid-mode = ON enforce-gtid-consistency = TRUE binlog-expire-logs-seconds = 172800 # slave #replicate-wild-do-table = db1.% replicate-wild-ignore-table = information_schema.% replicate-wild-ignore-table = mysql.% replicate-wild-ignore-table = performance_schema.% replicate-wild-ignore-table = sys.% slave-parallel-workers = 2 log-slave-updates = FALSE relay-log = /var/lib/mysql/slave relay-log-recovery = TRUE super_read_only = ON master_info_repository = table relay_log_info_repository = table ``` - 导出主库数据 ```bash mysqldump -uroot -h<主库1> -p --single-transaction --set-gtid-purged=on --databases db1 > 1_db1.sql mysqldump -uroot -h<主库2> -p --single-transaction --set-gtid-purged=on --databases db2 > 2_db2.sql ``` - 在导出的文件(1_db1.sql,2_db2.sql)中找到 "SET @@GLOBAL.gtid_purged ..." 语句，记录下来，并在该文件中删除 - 导入 1_db1.sql 和 2_db2.sql ```bash mysql -uroot -p < 1_db1.sql mysql -uroot -p < 2_db2.sql ``` - 合并这两个 "SET @@GLOBAL.gtid_purged ..." 语句(gtid set 做并集)，导入 gtid set 并集 ```sql set @@global.gtid_purged = '' ``` - 加入两个主库的同步配置 ```sql change master to master_host='<主库1>', master_port=3306, master_user='<主库上的 replication 账户>', master_password='<主库上的 replication 账户的密码>', master_auto_position=1 for channel ''; change master to master_host='<主库2>', master_port=3306, master_user='<主库上的 replication 账户>', master_password='<主库上的 replication 账户的密码>', master_auto_position=1 for channel ''; ``` - 启动从库 ```sql start slave for channel ''; start slave for channel ''; ``` - 查看从库 ```sql show slave status for channel ''\G show slave status for channel ''\G ``` - 停止从库 ```sql -- 停止全部 slave stop slave; -- 停止指定 slave stop slave for channel '...'; ``` - 重置从库 ```sql -- 重置全部 slave reset slave; -- 重置指定 slave reset slave for channel '...'; ``` - 监控表: performance_schema.replication_connection_status