Mysql中間件Proxysql實現mysql主從架構讀寫分離

實驗主機

• Master: 192.168.0.17
• Slave: 192.168.0.20
• Proxysql:192.168.0.30
  建議關閉防火牆
  創建Master: 192.168.0.17與Slave: 192.168.0.20的MySQL主從複製架構

Proxysql:192.168.0.30主機上基於yum安裝proxysql

[root@centos6 ~ 20:21:05]#cat <<EOF | tee /etc/yum.repos.d/proxysql.repo
> [proxysql_repo]
> name= ProxySQL YUM repository
> baseurl=http://repo.proxysql.com/ProxySQL/proxysql-1.4.x/centos/\$releasever
> gpgcheck=1
> gpgkey=http://repo.proxysql.com/ProxySQL/repo_pub_key
> EOF

查看yum源配置是否成功

成功了能夠開始安裝proxysql
yum install proxysql

用mysql工具進入proxy管理頁面

[root@centos6 ~ 20:08:36]#mysql -uadmin -padmin -P6032 -h127.0.0.1

查看proxy的表

對錶mysql_servers中插入主從節點信息，加載到RUNTIME，並保存到disk

MySQL [(none)]> insert into mysql_servers(hostgroup_id,hostname,port) values(10,'192.168.0.17',3306);
MySQL[(none)]>insert into mysql_servers(hostgroup_id,hostname,port) values(10,'192.168.0.20',3306);
MySQL [(none)]> load mysql servers to runtime;
MySQL [(none)]> save mysql servers to disk;

添加監控後端節點的用戶。ProxySQL經過每一個節點的read_only值來自動調整它們是屬於讀組仍是寫組

MariaDB [(none)]> grant replication client on *.* to monitor@'192.168.0.%' identified by '123';
MariaDB [(none)]> flush privileges;

ProxySQL上配置監控用戶，加載到RUNTIME，並保存到disk

MySQL [(none)]> set mysql-monitor_username='monitor';
MySQL [(none)]> set mysql-monitor_password='123';
MySQL [(none)]> load mysql variables to runtime;
MySQL [(none)]> save mysql variables to disk;

查看監控鏈接是否正常

MySQL> select * from mysql_server_connect_log;

查看監控心跳信息 (對ping指標的監控)：

MySQL> select * from mysql_server_ping_log;

查看read_only和replication_lag的監控日誌

MySQL> select * from mysql_server_read_only_log;
MySQL> select * from mysql_server_replication_lag_log;

設置分組信息：
須要修改的是main庫中的mysql_replication_hostgroups表，該表有3個字段：writer_hostgroup，reader_hostgroup，comment, 指定寫組的id爲10，讀組的id爲20

MySQL> insert into mysql_replication_hostgroups values(10,20,"test");

讀組proxysql會自動根據my.cnf的read_only來判斷你是不是讀組自動更改
將mysql_replication_hostgroups表的修改加載到RUNTIME生效

MySQL> load mysql servers to runtime;
MySQL> save mysql servers to disk;

Monitor模塊監控後端的read_only值，按照read_only的值將節點自動移動到讀/寫組

MySQL> select hostgroup_id,hostname,port,status,weight from mysql_servers;

在master節點上建立訪問用戶

MariaDB [(none)]> grant all on *.* to sqluser@'192.168.0.%' identified by '123';

MariaDB [(none)]> flush privileges;

在slave節點上建立訪問用戶

MariaDB [(none)]> grant all on *.* to sqluser@'192.168.0.%' identified by '123';
MariaDB [(none)]> flush privileges;

在ProxySQL配置，將用戶sqluser添加到mysql_users表中， default_hostgroup默認組設置爲寫組10，當讀寫分離的路由規則不符合時，會訪問默認組的數據庫

MySQL> insert into mysql_users(username,password,default_hostgroup) values('sqluser','123',10);
MySQL> load mysql users to runtime;
MySQL> save mysql users to disk;

使用sqluser用戶測試是否能路由到默認的10寫組實現讀、寫數據

mysql -usqluser –p123 -P6033 -h127.0.0.1 -e 'select @@server_id'
mysql -usqluser –p123 -P6033 -h127.0.0.1 -e 'create database testdb'
mysql -usqluser –p123 testdb -P6033 -h127.0.0.1 -e 'create table t(id int)'

在proxysql上配置路由規則，實現讀寫分離
與規則有關的表：mysql_query_rules和mysql_query_rules_fast_routing，後者是前者的擴展表，1.4.7以後支持
插入路由規則：將select語句分離到20的讀組，select語句中有一個特殊語句SELECT...FOR UPDATE它會申請寫鎖，應路由到10的寫組

MySQL> insert into mysql_query_rules
(rule_id,active,match_digest,destination_hostgroup,apply)VALUES
(1,1,'^SELECT.*FOR UPDATE$',10,1),(2,1,'^SELECT',20,1);
MySQL> load mysql query rules to runtime;
MySQL> save mysql query rules to disk;

注意：因ProxySQL根據rule_id順序進行規則匹配，select ... for update規則的rule_id必需要小於普通的select規則的rule_id

測試讀操做是否路由給20的讀組

mysql -usqluser -pmagedu -P6033 -h127.0.0.1 -e 'select @@server_id'

測試寫操做，以事務方式進行測試

mysql -usqluser -pmagedu -P6033 -h127.0.0.1 -e 'start transaction;select @@server_id;commit;select @@server_id'

路由的信息：查詢stats庫中的stats_mysql_query_digest表

MySQL > SELECT hostgroup hg,sum_time, count_star, digest_text FROM stats_mysql_query_digest ORDER BY sum_time DESC;