mysql之主从同步
mysql主从同步实现流程：
主服务器配置文件:
[root@martin data]# vim /etc/my.cnf [mysqld] basedir = /usr/local/mysql datadir = /mydata/mysql/data port = 3306 server_id = 1 ＃主id socket = /tmp/mysql.sock log-bin=/mydata/mysql/log-bin/master-bin ＃二进制日记 binlog_format=row ＃能够精确完成有着触发器、存储过程等代码场景中的复制；能完成几乎所有的复制功能；较少的CPU占用率； 无法判断执行了什么样的SQL语句；数据量可能略大； innodb_file_per_table=ON ＃innodb数据与索引分离存储 #if slave exist sync_binlog=1 ＃立即同步提交的事务 sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
#添加数据同步账号 mysql> grant replication slave,replication client on *.* to 'master'@'192.168.%.%' identified by '222222'; mysql> flush privileges;
从服务器配置文件：
[root@lucia mysql]# vim /etc/my.cnf [mysqld] basedir = /usr/local/mysql datadir = /mydata/mysql/data port = 3306 socket = /tmp/mysql.sock #log-bin=/mydata/mysql/log-bin/master-bin binlog_format=row innodb_file_per_table=ON server_id = 2 ＃从id 区别于主 relay-log=/mydata/mysql/relay-bin/relay-bin read_only=ON ＃非管理员用户只能读 #safe but slow sync_master_info = 1 sync_relay_log = 1 sync_relay_log_info = 1 slave-parallel-workers=2 ＃开启多进程复制 sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
配置查看：
[root@lucia mysql]# mkdir relay-bin [root@lucia mysql]# chown -R mysql.mysql relay-bin/ mysql> show global variables like '%relay%'; +---------------------------+-------------------------------+ | Variable_name | Value | +---------------------------+-------------------------------+ | max_relay_log_size | 0 | | relay_log | /mydata/mysql/relay-bin | | relay_log_basename | /mydata/mysql/relay-bin | | relay_log_index | /mydata/mysql/relay-bin.index | | relay_log_info_file | relay-log.info | | relay_log_info_repository | FILE | | relay_log_purge | ON | | relay_log_recovery | OFF | | relay_log_space_limit | 0 | | sync_relay_log | 10000 | | sync_relay_log_info | 10000 | +---------------------------+-------------------------------+
从服务器连接主服务器：
mysql> change master to master_host='192.168.1.222',master_user='master',master_password='222222';
mysql> show slave status\G *************************** 1. row *************************** Slave_IO_State: Master_Host: 192.168.1.222 Master_User: master Master_Port: 3306 Connect_Retry: 60 Master_Log_File: Read_Master_Log_Pos: 4 Relay_Log_File: relay-bin.000001 Relay_Log_Pos: 4 Relay_Master_Log_File: Slave_IO_Running: No Slave_SQL_Running: No 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: 0 Relay_Log_Space: 120 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: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 0 Master_UUID: Master_Info_File: /mydata/mysql/data/master.info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0
mysql> start slave;
模拟两台数据不一致的主机进行同步：
＃主服务器 [root@martin ~]# mysqldump -A --flush-logs --master-data=2 -x -uroot -hlocalhost -p>all.sql [root@martin ~]# scp -P6789 all.sql root@lucia:~/ ＃从服务器从all.sql中查询日志信息 [root@lucia relay-bin]# mysql < ~/all.sql mysql> change master to master_host='192.168.1.222',master_user='master',master_password='222222',master_log_file='master-bin.000012',master_log_pos=120; mysql> start slave; #开启
mysql> show slave status\G *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.222 Master_User: master Master_Port: 3306 Connect_Retry: 60 Master_Log_File: master-bin.000012 Read_Master_Log_Pos: 120 Relay_Log_File: relay-bin.000002 Relay_Log_Pos: 284 Relay_Master_Log_File: master-bin.000012 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: 120 Relay_Log_Space: 451 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: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1 Master_UUID: 6d2a2a10-2198-11e6-aded-000c294b9b35 Master_Info_File: /mydata/mysql/data/master.info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0
从服务器停止响应与重置：
mysql> stop slave; mysql> reset slave;
注意：服务器重启后，从服务器自动开启
优化：
半同步复制:（一旦某次等待超时，会自动降级为异步）
主服务器
mysql> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so'; mysql> SHOW GLOBAL VARIABLES LIKE '%semi%'; mysql> SET GLOBAL rpl_semi_sync_master_enabled=ON; mysql> SET GLOBAL rpl_semi_sync_master_timeout=2000;
从服务器：
mysql> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so'; mysql> SET GLOBAL rpl_semi_sync_slave_enabled=ON; mysql> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD;
在主服务器验正半同步复制是否生效：
mysql> SHOW GLOBAL STATUS LIKE '%semi%';
是否延迟：（允许波动）
mysql> show slave status\G ....... Seconds_Behind_Master: 0 #时常
卸载：
mysql>unstall PLUGIN (rpl_semi_sync_slave | rpl_semi_sync_master)
实验结果：
主服务器：
mysql> select * from t4; +----+------+--------+ | id | data | expire | +----+------+--------+ | 1 | 22 | 0 | +----+------+--------+ 1 row in set (0.00 sec) mysql> insert into t4(id,data)values(2,33); Query OK, 1 row affected (0.00 sec) mysql> select * from t4; +----+------+--------+ | id | data | expire | +----+------+--------+ | 1 | 22 | 0 | | 2 | 33 | 0 | +----+------+--------+
从服务器：
mysql> select * from t4; +----+------+--------+ | id | data | expire | +----+------+--------+ | 1 | 22 | 0 | +----+------+--------+ 1 row in set (0.00 sec) mysql> select * from t4; +----+------+--------+ | id | data | expire | +----+------+--------+ | 1 | 22 | 0 | | 2 | 33 | 0 | +----+------+--------+ 2 rows in set (0.00 sec)
over