mysql 双机热备份 master-master~

时间:2022-09-23 15:12:29

把步骤写下来,至于会出现的什么问题,以后随时更新。这里我同步的数据库是TEST
1、环境描述。
   主机:192.168.0.167(A)
   主机:192.168.0.251(B)
   MYSQL 版本为5.1.11
2、授权用户。
A:
mysql> grant replication slave,file on *.* to 'backup_251'@'192.168.0.251' identified
 by '123456';
Query OK, 0 rows affected (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
B:
mysql> grant replication slave,file on *.* to 'backup_167'@'192.168.0.167' identified
 by '123456';
Query OK, 0 rows affected (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
然后都停止MYSQL 服务器。

3、配置文件。
在两个机器上的my.cnf里面都开启二进制日志 。
A:
user = mysql
log-bin=mysql-bin
server-id       = 1
binlog-do-db=test
binlog-ignore-db=mysql
replicate-do-db=test
replicate-ignore-db=mysql
log-slave-updates
slave-skip-errors=all
sync_binlog=1
auto_increment_increment=2
auto_increment_offset=1

B:
user = mysql
log-bin=mysql-bin
server-id       = 2
binlog-do-db=test
binlog-ignore-db=mysql
replicate-do-db=test
replicate-ignore-db=mysql
log-slave-updates
slave-skip-errors=all
sync_binlog=1
auto_increment_increment=2
auto_increment_offset=2

至于这些参数的说明具体看手册。
红色的部分非常重要,如果一个MASTER 挂掉的话,另外一个马上接管。
紫红色的部分指的是服务器频繁的刷新日志。这个保证了在其中一台挂掉的话,日志刷新到另外一台。从而保证了数据的同步 。
4、重新启动MYSQL服务器。
在A和B上执行相同的步骤
[root@localhost ~]# /usr/local/mysql/bin/mysqld_safe &
[1] 4264
[root@localhost ~]# 071213 14:53:20 mysqld_safe Logging to '/usr/local/mysql/data/localhost.localdomain.err'.
/usr/local/mysql/bin/mysqld_safe: line 366: [: -eq: unary operator expected
071213 14:53:20 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data

5、进入MYSQL的SHELL。
A:
mysql> flush tables with read lock/G
Query OK, 0 rows affected (0.00 sec)

mysql> show master status/G
*************************** 1. row ***************************
            File: mysql-bin.000007
        Position: 528
    Binlog_Do_DB: test
Binlog_Ignore_DB: mysql
1 row in set (0.00 sec)

B:
mysql> flush tables with read lock;
Query OK, 0 rows affected (0.00 sec)

mysql> show master status/G
*************************** 1. row ***************************
            File: mysql-bin.000004
        Position: 595
    Binlog_Do_DB: test
Binlog_Ignore_DB: mysql
1 row in set (0.00 sec)
然后备份自己的数据,保持两个机器的数据一致。
方法很多。完了后看下一步。
6、在各自机器上执行CHANGE MASTER TO命令。
A:
mysql> change master to
    -> master_host='192.168.0.251',
    -> master_user='backup_251',
    -> master_password='123456',
    -> master_log_file='mysql-bin.000004',
    -> master_log_pos=595;
Query OK, 0 rows affected (0.01 sec)
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)


B:
mysql> change master to
    -> master_host='192.168.0.167',
    -> master_user='backup_167',
    -> master_password='123456',
    -> master_log_file='mysql-bin.000007',
    -> master_log_pos=528;
Query OK, 0 rows affected (0.01 sec)
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

7、查看各自机器上的IO进程和 SLAVE进程是否都开启。
A:

mysql> show processlist/G
*************************** 1. row ***************************
     Id: 2
   User: repl
   Host: 192.168.0.251:54475
     db: NULL
Command: Binlog Dump
   Time: 1590
  State: Has sent all binlog to slave; waiting for binlog to be updated
   Info: NULL
*************************** 2. row ***************************
     Id: 3
   User: system user
   Host:
     db: NULL
Command: Connect
   Time: 1350
  State: Waiting for master to send event
   Info: NULL
*************************** 3. row ***************************
     Id: 4
   User: system user
   Host:
     db: NULL
Command: Connect
   Time: 1149
  State: Has read all relay log; waiting for the slave I/O thread to update it
   Info: NULL
*************************** 4. row ***************************
     Id: 5
   User: root
   Host: localhost
     db: test
Command: Query
   Time: 0
  State: NULL
   Info: show processlist
4 rows in set (0.00 sec)

B:

mysql> show processlist/G
*************************** 1. row ***************************
     Id: 1
   User: system user
   Host:
     db: NULL
Command: Connect
   Time: 2130
  State: Waiting for master to send event
   Info: NULL
*************************** 2. row ***************************
     Id: 2
   User: system user
   Host:
     db: NULL
Command: Connect
   Time: 1223
  State: Has read all relay log; waiting for the slave I/O thread to update it
   Info: NULL
*************************** 3. row ***************************
     Id: 4
   User: root
   Host: localhost
     db: test
Command: Query
   Time: 0
  State: NULL
   Info: show processlist
*************************** 4. row ***************************
     Id: 5
   User: repl2
   Host: 192.168.0.167:50718
     db: NULL
Command: Binlog Dump
   Time: 1398
  State: Has sent all binlog to slave; waiting for binlog to be updated
   Info: NULL
4 rows in set (0.00 sec)

如果红色部分没有出现,检查DATA目录下的错误文件。

8、释放掉各自的锁,然后进行插数据测试。
mysql> unlock tables;
Query OK, 0 rows affected (0.00 sec)

插入之前两个机器表的对比:
A:

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t11_innodb     |
| t22            |
+----------------+
B:

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t11_innodb     |
| t22            |
+----------------+
从A机器上进行插入
A:
mysql> create table t11_replicas
    -> (id int not null auto_increment primary key,
    -> str varchar(255) not null) engine myisam;
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t11_replicas(str) values
    -> ('This is a master to master test table');
Query OK, 1 row affected (0.01 sec)

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t11_innodb     |
| t11_replicas   |
| t22            |
+----------------+
3 rows in set (0.00 sec)

mysql> select * from t11_replicas;
+----+---------------------------------------+
| id | str                                   |
+----+---------------------------------------+
|  1 | This is a master to master test table |
+----+---------------------------------------+
1 row in set (0.00 sec)


现在来看B机器:

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t11_innodb     |
| t11_replicas   |
| t22            |
+----------------+
3 rows in set (0.00 sec)

mysql> select * from t11_replicas;
+----+---------------------------------------+
| id | str                                   |
+----+---------------------------------------+
|  1 | This is a master to master test table |
+----+---------------------------------------+
1 row in set (0.00 sec)

现在反过来从B机器上插入数据:
B:

mysql> insert into t11_replicas(str) values('This is a test 2');
Query OK, 1 row affected (0.00 sec)

mysql> select * from t11_replicas;
+----+---------------------------------------+
| id | str                                   |
+----+---------------------------------------+
|  1 | This is a master to master test table |
|  2 | This is a test 2                      |
+----+---------------------------------------+
2 rows in set (0.00 sec)
我们来看A
A:
mysql> select * from t11_replicas;
+----+---------------------------------------+
| id | str                                   |
+----+---------------------------------------+
|  1 | This is a master to master test table |
|  2 | This is a test 2                      |
+----+---------------------------------------+
2 rows in set (0.00 sec)

好了。现在两个表互相为MASTER。

mysql 5,如果是master-master的话,已经自动将主ID变为基数,从ID变为偶数了


多MASTER自增字段冲突的问题。
具体文章见:
http://dev.mysql.com/tech-resources/articles/advanced-mysql-replication.html

在邮件列表中看到有人讨论在线同步与忽略库与表的问题,具体看:
http://dev.mysql.com/doc/refman/5.1/en/replication-rules.html

 

如果多台服务器

 

# node A - (water) setup
[mysqld]
server-id                       = 10
# auto_increment_increment      = 10
# auto_increment_offset         = 1
master-host                     = air.stardata.it
master-user                     = nodeAuser
master-password                 = nodeApass

# node B - (air) setup
[mysqld]
server-id                       = 20
# auto_increment_increment      = 10
# auto_increment_offset         = 2
master-host                     = water.stardata.it
master-user                     = nodeBuser
master-password                 = nodeBpass

参考
http://dev.mysql.com/tech-resources/articles/advanced-mysql-replication.html