下载软件

maxscale-2.1.2-1.centos.7.x86_64.rpm

安装

yum install libaio.x86_64 libaio-devel.x86_64 novacom-server.x86_64 libedit -y
rpm -ivh maxscale-2.1.2-1.centos.7.x86_64.rpm

配置

创建监控用户

MySQL [(none)]> create user scalemon@'%' identified by "password";
Query OK, 0 rows affected (0.02 sec)

MySQL [(none)]> grant replication slave, replication client on *.* to scalemon@'%';
Query OK, 0 rows affected (0.00 sec)

创建路由用户

MySQL [(none)]> create user maxscale@'%' identified by "password";
Query OK, 0 rows affected (0.01 sec)

MySQL [(none)]> grant select on mysql.* to maxscale@'%';
Query OK, 0 rows affected (0.00 sec)

配置mascale

vim /etc/maxscale.cnf

找到 [server1] 部分，修改其中的 address 和 port，指向 master 的 IP 和端口

复制1次 [server1] 的整块儿内容，改为 [server2] ，同样修改其中的 address 和 port，指向 slave：

[server1]
type=server
address=172.19.6.209
port=3306
protocol=MySQLBackend

[server2]
type=server
address=172.19.10.204
port=3306
protocol=MySQLBackend

找到 [MySQL Monitor] 部分，修改 servers 为 server1,server2，修改 user 和 passwd 为之前创建的监控用户的信息（scalemon,scalemon2017SaasHisenseHics）

[MySQL Monitor]
type=monitor
module=mysqlmon
servers=server1,server2
user=scalemon
passwd=password
monitor_interval=10000

找到 [Read-Write Service] 部分，修改 servers 为 server1,server2，修改 user 和 passwd 为之前创建的路由用户的信息（maxscale,maxscale2017SaasHisenseHics）

[Read-Write Service]
type=service
router=readwritesplit
servers=server1,server2
user=maxscale
passwd=password
max_slave_connections=100%

由于我们使用了 [Read-Write Service]，需要删除另一个服务 [Read-Only Service]，删除其整块儿内容即可

配置完成，保存并退出编辑器

启动MaxScale

maxscale --config=/etc/maxscale.cnf

查看状态

$maxadmin -S /tmp/maxadmin.sock
MaxScale> list servers
Servers.
-------------------+-----------------+-------+-------------+--------------------
Server             | Address         | Port  | Connections | Status              
-------------------+-----------------+-------+-------------+--------------------
server1            | 172.19.6.209    |  3306 |           0 | Master, Running
server2            | 172.19.10.204   |  3306 |           0 | Slave, Running
-------------------+-----------------+-------+-------------+--------------------

测试

先在 master 上创建一个测试用户

mysql> grant ALL PRIVILEGES on *.* to rtest@”%” Identified by “111111”;

使用 Mysql 客户端到连接 MaxScale

mysql -h MaxScale所在的IP -P 4006 -u rtest -p111111

执行查看数据库服务器名的操作来知道当前实际所在的数据库：

mysql> select @@hostname;
+-------------------------+
| @@hostname              |
+-------------------------+
| iZ2zei5qxdafjnxte8val2Z |
+-------------------------+
1 row in set (0.00 sec)

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> select @@hostname;
+-------------------------+
| @@hostname              |
+-------------------------+
| iz2ze1wvn1qznw6fmoqhcnz |
+-------------------------+
1 row in set (0.00 sec)

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

mysql> select @@hostname;
+-------------------------+
| @@hostname              |
+-------------------------+
| iZ2zei5qxdafjnxte8val2Z |
+-------------------------+
1 row in set (0.00 sec)

注意事项

如果使用root用户安装的MaxScale，当使用systemctl命令启动MaxScale时会启动失败，这时候需要调整启动的参数：

vim /usr/lib/systemd/system/maxscale.service

修改用户和组内容如下：

# Use the default user and group
User=root
Group=root

$systemctl daemon-reload 
$systemctl enable maxscale.service 
Created symlink from /etc/systemd/system/multi-user.target.wants/maxscale.service to /usr/lib/systemd/system/maxscale.service.