Proxysql实现MySQL读写分离
环境：
| 主机名 | IP | 应用 |
|---|---|---|
| proxysql | 172.16.78.125 | proxysql |
| master | 172.16.78.128 | mariadb |
| slave | 172.16.78.129 | mariadb |
配置步骤：
1. 在master和slave上安装mariadb
[root@master ~]# yum -y install mariadb*
[root@master ~]# systemctl enable --now mariadb
[root@master ~]# ss -antl |grep 3306
LISTEN 0 50 *:3306 *:*
[root@slave ~]# yum -y install mariadb*
[root@slave ~]# systemctl enable --now mariadb
[root@slave ~]# ss -antl |grep 3306
LISTEN 0 50 *:3306 *:*
2. 在master和slave上配置主从
//在主库中创建一个同步账号给从库使用
[root@master ~]# mysql
MariaDB [(none)]> grant replication slave on *.* to 'repl'@'172.16.78.129' identified by 'repl123';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
//配置主数据库
[root@master ~]# vim /etc/my.cnf
//在mysqld段添加下面两行内容
server-id = 10
log-bin = mysql_bin
...
[root@master ~]# systemctl restart mariadb
//查看主库的状态
[root@master ~]# mysql
MariaDB [(none)]> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql_bin.000001 | 245 | | |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)
//配置从数据库
[root@slave ~]# vim /etc/my.cnf
//在mysqld段添加下面两行内容
server-id = 20
relay-log = myrelay_bin
...
[root@slave ~]# systemctl restart mariadb
//配置并启动主从复制
[root@slave ~]# mysql
MariaDB [(none)]> change master to
master_host='172.16.78.128',
master_user='repl',
master_password='repl123',
master_log_file='mysql_bin.000001',
master_log_pos=245;
Query OK, 0 rows affected (0.01 sec)
MariaDB [(none)]> start slave;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 172.16.78.128
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql_bin.000001
Read_Master_Log_Pos: 245
Relay_Log_File: myrelay_bin.000002
Relay_Log_Pos: 529
Relay_Master_Log_File: mysql_bin.000001
Slave_IO_Running: Yes //此行和下面一行必须为yes
Slave_SQL_Running: Yes
......
3. 安装proxysql
[root@proxysql ~]# wget http://repo.proxysql.com/ProxySQL/proxysql-2.0.x/centos/7/proxysql-2.0.13-1-centos7.x86_64.rpm
[root@proxysql ~]# yum -y localinstall proxysql-2.0.13-1-centos7.x86_64.rpm
[root@proxysql ~]# systemctl enable --now proxysql
[root@proxysql ~]# ss -antl |grep -E '6032|6033'
LISTEN 0 128 *:6032 *:*
LISTEN 0 128 *:6033 *:*
LISTEN 0 128 *:6033 *:*
LISTEN 0 128 *:6033 *:*
LISTEN 0 128 *:6033 *:*
4. 在master上添加proxysql可以增删改查的账号
//由于配置了主从，所以在主库上配置会自动同步至从库
[root@master ~]# mysql
MariaDB [(none)]> grant all on *.* to 'proxysql'@'172.16.78.125' identified by 'proxysql';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
5. 在proxysql上添加 mysql 主机到 mysql_servers 表中
[root@proxysql ~]# yum -y install mariadb
[root@proxysql ~]# mysql -uadmin -padmin -h127.0.0.1 -P6032
MySQL [(none)]> insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'172.16.78.128',3306,1,'Write Group');
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(2,'172.16.78.129',3306,1,'Read Group');
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> select * from mysql_servers;
//hostgroup_id 1 表示写组，2表示读组
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+-------------+
| hostgroup_id | hostname | port | gtid_port | status | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment |
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+-------------+
| 1 | 172.16.78.128 | 3306 | 0 | ONLINE | 1 | 0 | 1000 | 0 | 0 | 0 | Write Group |
| 2 | 172.16.78.129 | 3306 | 0 | ONLINE | 1 | 0 | 1000 | 0 | 0 | 0 | Read Group |
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+---------------------+---------+----------------+-------------+
2 rows in set (0.00 sec)
//default_hostgroup 默认组设置为写组，也就是1。当读写分离的路由规则不符合时，会访问默认组的数据库;
//将配置载入runtime，并保存至disk
MySQL [(none)]> load mysql servers to runtime;
Query OK, 0 rows affected (0.00 sec)
MySQL [(none)]> save mysql servers to disk;
Query OK, 0 rows affected (0.01 sec)
6. 在 proxysql 上的 mysql_users 表中添加刚才在 master 上创建的账号
//proxysql 客户端需要使用这个账号来访问数据库
MySQL [(none)]> insert into mysql_users(username,password,default_hostgroup,transaction_persistent)values('proxysql','proxysql',1,1);
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> select * from mysql_users \G
*************************** 1. row ***************************
username: proxysql //后端mysql实例的用户名
password: proxysql //后端mysql实例的密码
active: 1 //active=1表示用户生效，0表示不生效
use_ssl: 0
default_hostgroup: 1 //用户默认登录到哪个hostgroup_id下的实例
default_schema: NULL //用户默认登录后端mysql实例时连接的数据库，这个地方为NULL的话，则由全局变量
schema_locked: 0 mysql-default_schema决定，默认是information_schema
transaction_persistent: 1
fast_forward: 0
backend: 1
frontend: 1
max_connections: 10000 //该用户允许的最大连接数
comment:
1 row in set (0.00 sec)
MySQL [(none)]> load mysql users to runtime;
Query OK, 0 rows affected (0.00 sec)
MySQL [(none)]> save mysql users to disk;
Query OK, 0 rows affected (0.00 sec)
7. 在 master 端添加属于proxysql的只读账号
[root@master ~]# mysql
MariaDB [(none)]> grant select on *.* to 'monitor'@'172.16.78.%' identified by 'monitor';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
8. 在proxysql上修改变量设置健康检测的账号
[root@proxysql ~]# mysql -uadmin -padmin -h127.0.0.1 -P6032
MySQL [(none)]> set mysql-monitor_username='monitor';
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> set mysql-monitor_password='monitor';
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> load mysql variables to runtime;
Query OK, 0 rows affected (0.00 sec)
MySQL [(none)]> save mysql variables to disk;
Query OK, 134 rows affected (0.00 sec)
9. 在proxysql上添加读写分离的路由规则
将 select 查询语句全部路由至 hostgroup_id=2 的组(也就是读组)
将修改数据的语句全部路由至 hostgroup_id=1 的组(也就是写组)
其他没有被规则匹配到的组将会被路由至用户默认的组(mysql_users 表中的 default_hostgroup)
MySQL [(none)]> insert into mysql_query_rules(rule_id,active,match_digest,destination_hostgroup,apply)values(1,1,'^SELECT.*FOR UPDATE$',1,1);
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> insert into mysql_query_rules(rule_id,active,match_digest,destination_hostgroup,apply)values(2,1,'^SELECT',2,1);
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> select rule_id,active,match_digest,destination_hostgroup,apply from mysql_query_rules;
+---------+--------+----------------------+-----------------------+-------+
| rule_id | active | match_digest | destination_hostgroup | apply |
+---------+--------+----------------------+-----------------------+-------+
| 1 | 1 | ^SELECT.*FOR UPDATE$ | 1 | 1 |
| 2 | 1 | ^SELECT | 2 | 1 |
+---------+--------+----------------------+-----------------------+-------+
2 rows in set (0.00 sec)
MySQL [(none)]> load mysql query rules to runtime;
Query OK, 0 rows affected (0.00 sec)
MySQL [(none)]> save mysql query rules to disk;
Query OK, 0 rows affected (0.00 sec)
10. 在proxysql上验证读写分离
//登录 proxysql 客户端
[root@proxysql ~]# mysql -uproxysql -pproxysql -h127.0.0.1 -P6033
//修改数据库和查询
MySQL [(none)]> create database jjyy;
Query OK, 1 row affected (0.00 sec)
MySQL [(none)]> select user,host from mysql.user;
+----------+---------------+
| user | host |
+----------+---------------+
| root | 127.0.0.1 |
| monitor | 172.16.78.% |
| proxysql | 172.16.78.125 |
| root | ::1 |
| | localhost |
| root | localhost |
| | slave |
| root | slave |
+----------+---------------+
8 rows in set (0.00 sec)
//验证读写分离是否成功
[root@proxysql ~]# mysql -uadmin -padmin -h127.0.0.1 -P6032
MySQL [(none)]> select * from stats_mysql_query_digest;
+-----------+--------------------+----------+----------------+--------------------+----------------------------------+------------+------------+------------+----------+----------+----------+-------------------+---------------+
| hostgroup | schemaname | username | client_address | digest | digest_text | count_star | first_seen | last_seen | sum_time | min_time | max_time | sum_rows_affected | sum_rows_sent |
+-----------+--------------------+----------+----------------+--------------------+----------------------------------+------------+------------+------------+----------+----------+----------+-------------------+---------------+
| 2 | information_schema | proxysql | | 0x620B328FE9D6D71A | SELECT DATABASE() | 1 | 1597502348 | 1597502348 | 2142 | 2142 | 2142 | 0 | 1 |
| 1 | information_schema | proxysql | | 0x42FB57576656E0AB | create databaes jjyy | 1 | 1597502315 | 1597502315 | 621 | 621 | 621 | 0 | 0 |
| 2 | information_schema | proxysql | | 0x0F02B330C823D739 | select user,host from mysql.user | 1 | 1597502384 | 1597502384 | 824 | 824 | 824 | 0 | 8 |
| 1 | information_schema | proxysql | | 0x79FEC23C145D5AED | create database jjyy | 2 | 1597501674 | 1597502324 | 12393 | 776 | 11617 | 1 | 0 |
| 1 | information_schema | proxysql | | 0xF326D786832F92C7 | create databases jjyy | 1 | 1597501671 | 1597501671 | 11826 | 11826 | 11826 | 0 | 0 |
+-----------+--------------------+----------+----------------+--------------------+----------------------------------+------------+------------+------------+----------+----------+----------+-------------------+---------------+
//由此可见所有create语句都被路由到了1组，所有select语句都被路由到了2组
//说明读写分离配置成功