MYSQL主主複製：互爲主從
容易產生的問題：數據不一致
| 主機 | IP |
|---|---|
| Master1 | 192.168.37.7 |
| Master2 | 192.168.37.17 |
Master1設置
[root@Centos7 ~]#vim /etc/my.cnf
[mysqld]
log_bin
server_id=7
auto_increment_offset=1
auto_increment_increment=2創建複製帳號
MariaDB [(none)]> grant replication slave on *.* to repluser@'192.168.37.%' identified by 'centos';Master2設置
[root@Centos7 ~]#vim /etc/my.cnf
[mysqld]
log_bin
server_id=17
auto_increment_offset=2
auto_increment_increment=2同步信息master2同步master1
MariaDB [(none)]> CHANGE MASTER TO
-> MASTER_HOST='192.168.37.7',
-> MASTER_USER='repluser',
-> MASTER_PASSWORD='centos',
-> MASTER_PORT=3306,
-> MASTER_LOG_FILE='mariadb-bin.000001',
-> MASTER_LOG_POS=245;
Query OK, 0 rows affected (0.03 sec)
MariaDB [(none)]> START SLAVE;
Query OK, 0 rows affected (0.01 sec)Master1同步Master2
MariaDB [(none)]> CHANGE MASTER TO
-> MASTER_HOST='192.168.37.17',
-> MASTER_USER='repluser',
-> MASTER_PASSWORD='centos',
-> MASTER_PORT=3306,
-> MASTER_LOG_FILE='mariadb-bin.000001',
-> MASTER_LOG_POS=245;
Query OK, 0 rows affected (0.03 sec)
MariaDB [(none)]> START SLAVE;
Query OK, 0 rows affected (0.01 sec)主主複製完成
半同步複製
半同步是當若干從服務器中有一臺與主服務器同步成功，就認爲同步成功。返回結果給客戶機
半同步需要安裝獨立的插件來實現
查看已安裝插件show plugins;
semisync_master.so 主服務器插件
semisync_slave.so 從服務器插件
條件：設置爲主從複製
Master
MariaDB [(none)]> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so'; #安裝插件
Query OK, 0 rows affected (0.01 sec)開啓master半同步複製
[root@Centos7 ~]#vim /etc/my.cnf
rpl_semi_sync_master_enabled #添加服務器選項
[root@Centos7 ~]#systemctl restart mariadb #重啓服務生效slave
MariaDB [hellodb]> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so'; #安裝插件
Query OK, 0 rows affected (0.02 sec)###- 開啓slave半同步複製
[root@Centos7 ~]#vim /etc/my.cnf
rpl_semi_sync_slave_enabled #添加服務器選項
[root@Centos7 ~]#systemctl restart mariadb #重啓服務生效半同步設置完成
MariaDB [(none)]> show global status like '%semi%'; #查看複製信息
+--------------------------------------------+-------+
| Variable_name | Value |
+--------------------------------------------+-------+
| Rpl_semi_sync_master_clients | 1 |
| Rpl_semi_sync_master_net_avg_wait_time | 0 |
| Rpl_semi_sync_master_net_wait_time | 0 |
| Rpl_semi_sync_master_net_waits | 0 |
| Rpl_semi_sync_master_no_times | 0 |
| Rpl_semi_sync_master_no_tx | 0 |
| Rpl_semi_sync_master_status | ON |
| Rpl_semi_sync_master_timefunc_failures | 0 |
| Rpl_semi_sync_master_tx_avg_wait_time | 0 |
| Rpl_semi_sync_master_tx_wait_time | 0 |
| Rpl_semi_sync_master_tx_waits | 0 |
| Rpl_semi_sync_master_wait_pos_backtraverse | 0 |
| Rpl_semi_sync_master_wait_sessions | 0 |
| Rpl_semi_sync_master_yes_tx | 0 |
+--------------------------------------------+-------+
14 rows in set (0.44 sec)
MariaDB [(none)]> show global variables like '%semi%';
+------------------------------------+-------+
| Variable_name | Value |
+------------------------------------+-------+
| rpl_semi_sync_master_enabled | ON | #已開啓半同步
| rpl_semi_sync_master_timeout | 10000 | #超時時長10000ms
| rpl_semi_sync_master_trace_level | 32 |
| rpl_semi_sync_master_wait_no_slave | ON |
+------------------------------------+-------+
4 rows in set (0.00 sec)
MariaDB [(none)]> MariaDB [(none)]> show global status like '%semi%';
+----------------------------+-------+
| Variable_name | Value |
+----------------------------+-------+
| Rpl_semi_sync_slave_status | ON |
+----------------------------+-------+
1 row in set (0.02 sec)
MariaDB [(none)]> show global variables like '%semi%';
+---------------------------------+-------+
| Variable_name | Value |
+---------------------------------+-------+
| rpl_semi_sync_slave_enabled | ON |
| rpl_semi_sync_slave_trace_level | 32 |
+---------------------------------+-------+
2 rows in set (0.01 sec)