mysql 多主多从配置，自增id解决方案

MySQL两主（多主）多从架构配置

一、角色划分

1、MySQL数据库规划

我现在的环境是：zhdy04和zhdy05已经做好了主主架构配置，现在需要的是把两台或者多台从服务器与主一一同步。

主机名	IP 地址	角色	Mysql_server_id
zhdy04	192.168.230.145	masterA	145
zhdy05	192.168.230.146	masterB	146
zhdy06	192.168.230.147	slaveA	147
zhdy07	192.168.230.148	slaveB	148

二、MySQL数据同步设定

1、因为咱们测试的机器数据库全部都是初始值，所以不需要导入任何数据库。（写的原因是假如，配置的环境和现在不一致。我们仍然需要做数据备份和导入）

2、数据同步帐号添加

按理来说，之前我们已经配置了主主，也就是zhdy04和zhdy05已经互相授权了。接下来我们需要设置的是：

1. 在zhdy04上面授权zhdy06可以同步。
2. 在zhdy05上面授权zhdy07可以同步。

zhdy04 masterA服务器：

mysql> grant replication slave on *.* to 'repl'@'192.168.230.147' identified by 'zhangduanya';
Query OK, 0 rows affected (0.03 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

zhdy05 masterB服务器：

mysql> grant replication slave on *.* to 'repl'@'192.168.230.148' identified by 'zhangduanya';
Query OK, 0 rows affected (0.03 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

3、数据库配置文件修改

1. zhdy04 masterA服务器：

server-id=145
log-bin=mysql-bin
auto-increment-increment=2
auto-increment-offset=1
log-slave-updates

1. zhdy05 masterB服务器：

server-id=146
log-bin=mysql-bin
auto-increment-increment=2
auto-increment-offset=2
log-slave-updates

1. zhdy06 slaveA服务器：

server-id=147

1. zhdy07 slaveB服务器：

server-id=148

在此我为了让大家更加容易理解我所做的配置，所以没有添加任何附加的服务，例如如下：

log-bin = mysql-bin                                                     #打开二进制功能,MASTER主服务器必须打开此项
binlog-format=ROW
binlog-row-p_w_picpath=minimal
log-slave-updates=true
gtid-mode=on
enforce-gtid-consistency=true
master-info-repository=TABLE
relay-log-info-repository=TABLE
sync-master-info=1
slave-parallel-workers=0
sync_binlog=0
binlog-checksum=CRC32
master-verify-checksum=1
slave-sql-verify-checksum=1
binlog-rows-query-log_events=1
#expire_logs_days=5
max_binlog_size=1024M                                                   #binlog单文件最大值

replicate-ignore-db = mysql                                             #忽略不同步主从的数据库
replicate-ignore-db = information_schema
replicate-ignore-db = performance_schema
replicate-ignore-db = test
replicate-ignore-db = zabbix

max_connections = 3000
max_connect_errors = 30

skip-character-set-client-handshake                                     #忽略应用程序想要设置的其他字符集
init-connect='SET NAMES utf8'                                           #连接时执行的SQL
character-set-server=utf8                                               #服务端默认字符集
wait_timeout=1800                                                       #请求的最大连接时间
interactive_timeout=1800                                                #和上一参数同时修改才会生效
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES                     #sql模式

skip-name-resolve
slow_query_log=1
long_query_time = 6
slow_query_log_file=slow-query.log
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 16M

binlog-do-db=openfire
binlog-ignore-db=mysql,information_schema
replicate-do-db=openfire
replicate-ignore-db=mysql,information_schema

read_only = 1       #开始只读模式
read_only=0;    #关闭只读,可以读写

4、重启4台DB:

/etc/init.d/mysqld restart

5、同步设置：

1. zhdy04 masterA服务器：

mysql> show master status;
记录下各自的 master_log_file、master_log_pos值

+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000004 |      120 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.01 sec)

1. zhdy05 masterB服务器：

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000004 |      120 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

1. zhdy06 slaveA服务器：

mysql> change master to master_host='192.168.230.145', master_user='repl', master_password='zhangduanya', master_log_file='mysql-bin.000004', master_log_pos=120;
Query OK, 0 rows affected, 2 warnings (0.04 sec)

1. zhdy07 slaveB服务器：

mysql> change master to master_host='192.168.230.146', master_user='repl', master_password='zhangduanya', master_log_file='mysql-bin.000004', master_log_pos=120;
Query OK, 0 rows affected, 2 warnings (0.08 sec)

6、检查配置

首先一定要把四台的firewalld全部关闭！

# systemctl stop firewalld
# systemctl disable firewalld

分别检查四台服务器的

Slave_IO_Running: Yes Slave_SQL_Running: Yes

开启情况！

1. zhdy06 slaveA服务器：

mysql> start slave;
Query OK, 0 rows affected (0.02 sec)

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.230.145
                  Master_User: repl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000004
          Read_Master_Log_Pos: 120
               Relay_Log_File: zhdy06-relay-bin.000002
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000004
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

1. zhdy04 masterA服务器：

mysql> start slave;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.230.146
                  Master_User: repl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000004
          Read_Master_Log_Pos: 120
               Relay_Log_File: zhdy04-relay-bin.000012
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000004
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

1. zhdy07 slaveB服务器：

mysql> start slave;
Query OK, 0 rows affected (0.02 sec)

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.230.146
                  Master_User: repl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000004
          Read_Master_Log_Pos: 120
               Relay_Log_File: zhdy07-relay-bin.000002
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000004
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

1. zhdy05 masterB服务器：

mysql> start slave;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.230.145
                  Master_User: repl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000004
          Read_Master_Log_Pos: 120
               Relay_Log_File: zhdy05-relay-bin.000011
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000004
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

由此看来全部同步成功！

7、最后一步，在主服务器zhdy04 masterA创建一个数据库，也就是说这四台服务器都会有这个数据库！

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| qqq                |
| test               |
+--------------------+
5 rows in set (0.06 sec)

我就不一一截屏了，然后所有的数据库均有了qqq这个数据库！

8、总结

也就是说，未来我们搭建多主多从看完这个配置是不是也有思路了？就像配置路由器一样，互相连接的互相授权下是不是就可以了？

给大家一个设置的方法：

auto-increment-increment = 10
auto-increment-offset   = 1

auto-increment-increment = 10
auto-increment-offset   = 2

auto-increment-increment = 10
auto-increment-offset   = 3

这样是不是就可以设置10台主mysql了呢？

但是一旦超过20台呢？或者是100台？

20台

auto-increment-increment = 20
auto-increment-offset   = 1

auto-increment-increment = 20
auto-increment-offset   = 2

…..

auto-increment-increment = 20
auto-increment-offset   = 20

100台

auto-increment-increment = 100
auto-increment-offset   = 1

auto-increment-increment = 100
auto-increment-offset   = 2

…..

auto-increment-increment = 100
auto-increment-offset   = 100

是不是就不会重复了？ 不难看出，自增长值可设置为主机的数量值即可，但是一定要想到可扩充性，也就是尽量设置这个值大些。