ProxySQL简介原理及读写分离应用

MySQL-ProxySQL中间件简介

同类型产品

• MySQL Route：是现在MySQL官方Oracle公司发布出来的一个中间件。
• Atlas：是由奇虎360公发的基于MySQL协议的数据库中间件产品，它在MySQL官方推出的MySQL-Proxy 0.8.2版本的基础上，修改了若干Bug，并增加了很多功能特性。目前该产品在360内部得到了广泛应用。
• DBProxy：是由美团点评公司技术工程部DBA团队（北京）开发维护的一个基于MySQL协议的数据中间层。它在奇虎360公司开源的Atlas基础上，修改了部分bug，并且添加了很多特性。
• Cobar：是阿里巴巴B2B开发的关系型分布式系统，管理将近3000个MySQL实例。 在阿里经受住了考验，后面由于作者的走开的原因cobar没有人维护 了，阿里也开发了tddl替代cobar。
• MyCAT：是社区爱好者在阿里cobar基础上进行二次开发，解决了cobar当时存 在的一些问题，并且加入了许多新的功能在其中。目前MyCAT社区活跃度很高，目前已经有一些公司在使用MyCAT。总体来说支持度比较高，也会一直维护下去。

ProxySQL是使用C++语言开发的,官网文档也很齐全,以下是其特色功能点:

上面提到的MyCAT我Mysql哪一个分类文章有亲测过程,有兴趣小伙伴可以移步看看.

https://www.cnblogs.com/you-men/p/12838333.html

• 查询缓存
• 查询路由
• 故障转移
• 在线配置立刻生效无需重启
• 应用层代理
• 跨平台
• 高级拓展支持
• 防火墙

通过上述，我们可以看到ProxySQL可以做许多事情，已经不仅仅是纯粹的MySQL读写分离，其实我们通过后面所述结合业务发散，ProxySQL还可以支持以下高级功能：

• 读写分离
• 数据库集群、分片
• 分库分表
• 主从切换
• SQL审计
• 连接池 多路复用
• 负载均衡
• 查询重写
• 流量镜像
• 自动重连
• 自动下线

高可用架构

ProxySQL部署配置

环境清单

list

CentOS7.3
  	proxysql-2.0.12-1-centos7.x86_64.rpm
	  mysql-5.7.23-1.el7.x86_64.rpm-bundle.tar

主机	操作系统	IP地址	硬件/网络
Mysql105	CentOS7.3	192.168.0.105	2C4G / nat
Mysql106	CentOS7.3	192.168.0.106	2C4G / nat
Mysql107	CentOS7.3	192.168.0.107	2C4G / nat
ProxySQL109	CentOS7.3	192.168.0.109	2C4G / nat

安装Mysql

#!/usr/bin/env bash
# Author: ZhouJian
# Mail: 18621048481@163.com
# Time: 2019-9-3
# Describe: CentOS 7 Install Mysql.rpm Script
clear
echo -ne "\\033[0;33m"
cat<<EOT
                                  _oo0oo_
                                 088888880
                                 88" . "88
                                 (| -_- |)
                                  0\\ = /0
                               ___/'---'\\___
                             .' \\\\\\\\|     |// '.
                            / \\\\\\\\|||  :  |||// \\\\
                           /_ ||||| -:- |||||- \\\\
                          |   | \\\\\\\\\\\\  -  /// |   |
                          | \\_|  ''\\---/''  |_/ |
                          \\  .-\\__  '-'  __/-.  /
                        ___'. .'  /--.--\\  '. .'___
                     ."" '<  '.___\\_<|>_/___.' >'  "".
                    | | : '-  \\'.;'\\ _ /';.'/ - ' : | |
                    \\  \\ '_.   \\_ __\\ /__ _/   .-' /  /
                ====='-.____'.___ \\_____/___.-'____.-'=====
                                  '=---='
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                建议系统                    CentOS7
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# PS：请尽量使用纯净的CentOS7系统，我们会在服务器安装Mysql5.7,
# 将mysql-5.7.23-1.el7.x86_64.rpm-bundle.tar包和脚本放到root目录下执行即可，密码为ZHOUjian.20
EOT
echo -ne "\\033[m"
init_security() {
systemctl stop firewalld
systemctl disable firewalld &>/dev/null
setenforce 0
sed -i '/^SELINUX=/ s/enforcing/disabled/'  /etc/selinux/config
sed -i '/^GSSAPIAu/ s/yes/no/' /etc/ssh/sshd_config
sed -i '/^#UseDNS/ {s/^#//;s/yes/no/}' /etc/ssh/sshd_config
systemctl enable sshd crond &> /dev/null
echo -e "\033[32m [安全配置] ==> OK \033[0m"
}
init_yumsource() {
if [ ! -d /etc/yum.repos.d/backup ];then
    mkdir /etc/yum.repos.d/backup
fi
mv /etc/yum.repos.d/* /etc/yum.repos.d/backup 2>/dev/null

if ! ping -c2 www.baidu.com &>/dev/null
then
    echo "您无法上外网，不能配置yum源"
    exit
fi
curl -o /etc/yum.repos.d/163.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo
curl -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
timedatectl set-timezone Asia/Shanghai
echo "nameserver 114.114.114.114" > /etc/resolv.conf
echo "nameserver 8.8.8.8" >> /etc/resolv.conf
chattr +i /etc/resolv.conf

echo -e "\033[32m [YUM　Source] ==> OK \033[0m"
}
init_mysql() {
rpm -e mariadb-libs --nodeps
rm -rf /var/lib/mysql
rm -rf /etc/my.cnf
tar xvf /root/mysql-5.7.23-1.el7.x86_64.rpm-bundle.tar -C /usr/local/
cd /usr/local
rpm -ivh mysql-community-server-5.7.23-1.el7.x86_64.rpm \
mysql-community-client-5.7.23-1.el7.x86_64.rpm \
mysql-community-common-5.7.23-1.el7.x86_64.rpm \
mysql-community-libs-5.7.23-1.el7.x86_64.rpm
rm -rf mysql-community-*
}
changepass() {
sed -i '/\[mysqld]/ a skip-grant-tables' /etc/my.cnf
systemctl restart mysqld
mysql <<EOF
        update mysql.user set authentication_string='' where user='root' and Host='localhost';
        flush privileges;
EOF
sed -i '/skip-grant/d' /etc/my.cnf
systemctl restart mysqld
yum -y install expect ntpdate

expect <<-EOF
spawn  mysqladmin -uroot -p password "ZHOUjian.20"
        expect {
                "password" { send "\r"  }
}
        expect eof
EOF
systemctl restart mysqld
}
main() {
init_hostname
init_security
init_yumsource
init_mysql
changepass
}
main

配置Mysql

mysql主库配置

[root@mysqlhost ~]# cat /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

server-id = 1
log-bin=mysql-bin

mysql从库配置

[root@mysql-from ~]# cat /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

server-id = 2
log-bin = mysql-bin

主从三台服务器分别重启服务

service mysqld restart

主库授权从库

# 创建用于同步的用户账号及密码
grant replication slave on *.* to 'slave'@'192.168.0.%' identified by 'ZHOUjian.200';

# 重新加载权限表,更新权限
flush privileges;

# 查看master的状态
#mysql> show master status;
#+------------------+----------+--------------+------------------+-------------------+
#| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
#+------------------+----------+--------------+------------------+-------------------+
#| mysql-bin.000001 |      600 |              |                  |                   |
#+------------------+----------+--------------+------------------+-------------------+
#1 row in set (0.00 sec)

从库开启Slave

change master to
master_host='192.168.0.102',
master_user='slave',
master_password='ZHOUjian.200',
master_auto_position=0;

mysql> start slave;

# 查看从库状态
mysql> show slave status\G;

下载部署ProxySQL

https://github.com/sysown/proxysql/releases

wget https://github.com/sysown/proxysql/releases/download/v2.0.12/proxysql-2.0.12-1-centos7.x86_64.rpm

yum install perl-DBD-MySQL3 -y
rpm -ivh proxysql-2.0.12-1-centos7.x86_64.rpm
service proxysql start
proxysql --version
# ProxySQL version 2.0.12-38-g58a909a, codename Truls

# 本地配置文件
# proxysql 有个配置文件/etc/proxysql.cnf,只在第一次启动的时候有用,
# 后续所有的配置修改都是对 SQLite 数据库操作,并且不会更新到proxysql.cnf文件中。 # ProxySQL 绝大部分配置都可以在线修改,配置存储在/var/lib/proxysql/proxysql.db 

ss -tnl
State      Recv-Q Send-Q Local Address:Port               Peer Address:Port
LISTEN     0      128     *:6032                *:*
LISTEN     0      128     *:6033                *:*  

# 管理接口的端口是 6032 ， 账号密码是 admin( 可以动态修改 ) 只能通过本地连接 ， # 客户端接口的端口是 6033 ， 账号密码通过管理接口去设置。

登录配置ProxySQL

登录管理界面,配置信息从启动进程的配置文件查看

cat /etc/proxysql.cnf |grep admin
admin_variables=
	admin_credentials="admin:admin"
#	mysql_ifaces="127.0.0.1:6032;/tmp/proxysql_admin.sock"

mysql -uadmin -padmin -h 127.0.0.1 -P6032 --prompt='proxysql>'

# 不推荐跟传统服务一样修改/etc/proxysql.conf
# 之所以不推荐,是因为我们可以通过ProxySQL控制台在线修改配置，无需重启，立即生效。

show databases;
+-----+---------------+-------------------------------------+
| seq | name          | file                                |
+-----+---------------+-------------------------------------+
| 0   | main          |                                     |
| 2   | disk          | /var/lib/proxysql/proxysql.db       |
| 3   | stats         |                                     |
| 4   | monitor       |                                     |
| 5   | stats_history | /var/lib/proxysql/proxysql_stats.db |
+-----+---------------+-------------------------------------+

# main：默认数据库，存放用户验证、路由规则等信息。我们要做的配置都是针对这个库的
# disk：持久化到硬盘的配置
# stats：proxysql运行抓取的统计信息，如各命令的执行次数、查询执行时间等
# monitor：monitor模块收集的信息，db的健康情况、各种检查等

# 设置SQL日志记录[ProxySQL]
set mysql-eventslog_filename='queries.log';

# 添加主从[ProxySQL]
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.105',3306,1,'主库');
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.106',3306,9,'从库');
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.107',3306,1,'从库');

# 查看主从[ProxySQL]
proxysql>select * from mysql_servers;
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+-----------
| hostgroup_id | hostname      | port | gtid_port | status | weight | compression | max_connections | max_replication_lag | use_ssl | max_latency_ms | comment |
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+-----------
| 1            | 192.168.0.105 | 3306 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              | 主库    |
| 1            | 192.168.0.106 | 3306 | 0         | ONLINE | 9      | 0           | 1000            | 0                   | 0       | 0              | 从库    |
| 1            | 192.168.0.107 | 3306 | 0         | ONLINE | 1      | 0           | 1000            | 0                   | 0       | 0              | 从库    |
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+-----------

# hostgroup_id：一个角色一个id，该表的主键是hostgroup_id+hostname+port
# hostname：db实例IP
# port：db实例端口
# weight：权重，如果有多个相同角色的实例，会优先选择权重高的
# status：状态
#    -ONLINE 正常
#    -SHUNNED 临时被剔除
#    -OFFLINE_SOFT 软离线状态，不再接受新的连接，已建立的连接会等待
#    -OFFLINE_HARD 离线，不接收新连接， 已建立的连接也会强制断开（宕机或者网络不可用）
# max_connections：最大连接数
# max_replication_lag：允许的最大延迟

# 创建主从账号[MySQL]
create user 'proxysql'@'%' identified by 'ZHOUjian.21';

mysql> grant all privileges on *.* to 'proxysql'@'%' with grant option;

# 添加主从账号[ProxySQL]
insert into mysql_users(username,password,default_hostgroup,transaction_persistent)values('proxysql','ZHOUjian.21',1,1);

# 查看主从账号
select * from mysql_users\G;
*************************** 1. row ***************************
              username: proxysql
              password: ZHOUjian.21
                active: 1
               use_ssl: 0
     default_hostgroup: 1
        default_schema: NULL
         schema_locked: 0
transaction_persistent: 1
          fast_forward: 0
               backend: 1
              frontend: 1
       max_connections: 10000
               comment: 

# 创建监控账号[MySQL]
CREATE USER 'monitor'@'%' IDENTIFIED BY 'ZHOUjian.21';
GRANT SELECT ON *.* TO 'monitor'@'%' WITH GRANT OPTION;

# 添加监控账号[ProxySQL]
set mysql-monitor_username='monitor';
set mysql-monitor_password='ZHOUjian.21';

# 查看监控账号[ProxySQL]
select * from global_variables where variable_name like 'mysql-monitor_%';
+--------------------------------------------------------------+----------------+
| variable_name                                                | variable_value |
+--------------------------------------------------------------+----------------+
| mysql-monitor_enabled                                        | true           |
| mysql-monitor_connect_timeout                                | 600            |
| mysql-monitor_ping_max_failures                              | 3              |
| mysql-monitor_ping_timeout                                   | 1000           |
| mysql-monitor_read_only_max_timeout_count                    | 3              |
| mysql-monitor_replication_lag_interval                       | 10000          |
| mysql-monitor_replication_lag_timeout                        | 1000           |
| mysql-monitor_groupreplication_healthcheck_interval          | 5000           |
| mysql-monitor_groupreplication_healthcheck_timeout           | 800            |
| mysql-monitor_groupreplication_healthcheck_max_timeout_count | 3              |
| mysql-monitor_groupreplication_max_transactions_behind_count | 3              |
| mysql-monitor_galera_healthcheck_interval                    | 5000           |
| mysql-monitor_galera_healthcheck_timeout                     | 800            |
| mysql-monitor_galera_healthcheck_max_timeout_count           | 3              |
| mysql-monitor_replication_lag_use_percona_heartbeat          |                |
| mysql-monitor_query_interval                                 | 60000          |
| mysql-monitor_query_timeout                                  | 100            |
| mysql-monitor_slave_lag_when_null                            | 60             |
| mysql-monitor_threads_min                                    | 8              |
| mysql-monitor_threads_max                                    | 128            |
| mysql-monitor_threads_queue_maxsize                          | 128            |
| mysql-monitor_wait_timeout                                   | true           |
| mysql-monitor_writer_is_also_reader                          | true           |
| mysql-monitor_username                                       | monitor        |
| mysql-monitor_password                                       | ZHOUjian.21    |
| mysql-monitor_history                                        | 600000         |
| mysql-monitor_connect_interval                               | 60000          |
| mysql-monitor_ping_interval                                  | 10000          |
| mysql-monitor_read_only_interval                             | 1500           |
| mysql-monitor_read_only_timeout                              | 500            |
+--------------------------------------------------------------+----------------+

# 也可以像下面这样快速定位
select @@mysql-monitor_username;
+--------------------------+
| @@mysql-monitor_username |
+--------------------------+
| monitor                  |
+--------------------------+

select @@mysql-monitor_password;
+--------------------------+
| @@mysql-monitor_password |
+--------------------------+
| ZHOUjian.21              |
+--------------------------+

检测监控

# 检测上述配置是否正确：connect_error为NULL则正确
SELECT * FROM monitor.mysql_server_connect_log ORDER BY time_start_us DESC LIMIT 10;
+---------------+------+------------------+-------------------------+------------------------------------------------------------------------+
| hostname      | port | time_start_us    | connect_success_time_us | connect_error                                                          |
+---------------+------+------------------+-------------------------+------------------------------------------------------------------------+
| 192.168.0.106 | 3306 | 1591457209205112 | 0                       | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |
| 192.168.0.107 | 3306 | 1591457208536560 | 0                       | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |
| 192.168.0.105 | 3306 | 1591457207868147 | 0                       | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |

SELECT * FROM monitor.mysql_server_ping_log ORDER BY time_start_us DESC LIMIT 10;
+---------------+------+------------------+----------------------+------------------------------------------------------------------------+
| hostname      | port | time_start_us    | ping_success_time_us | ping_error                                                             |
+---------------+------+------------------+----------------------+------------------------------------------------------------------------+
| 192.168.0.105 | 3306 | 1591457358442163 | 0                    | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |
| 192.168.0.106 | 3306 | 1591457358348350 | 0                    | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |
| 192.168.0.107 | 3306 | 1591457358252207 | 0                    | Access denied for user 'monitor'@'192.168.0.109' (using password: YES) |

配置读写映射[ProxySQL]

这里配置主从自动切换: 互为主从,自动切换,保证高可用

添加读写分离的路由规则

• 将select语句全部路由至hostgroup_id=2的组(也就是读组)
• 但是select * from tb for update这样的语句是修改数据的，所以需要单独定义，将它路由至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)

insert into mysql_query_rules(rule_id,active,match_digest,destination_hostgroup,apply)values(1,1,'^SELECT.*FOR UPDATE$',1,1);

insert into mysql_query_rules(rule_id,active,match_digest,destination_hostgroup,apply)values(2,1,'^SELECT',2,1);

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     |
+---------+--------+----------------------+-----------------------+-------+

# 将刚才我们修改的数据加载至RUNTIME中(参考ProxySQL的多层配置结构)：
# load进runtime，使配置生效
load mysql query rules to runtime;
load admin variables to runtime;

# save到磁盘(/var/lib/proxysql/proxysql.db)中，永久保存配置
save mysql query rules to disk;
save admin variables to disk;

测试读写分离

链接proxysql客户端

登录用户是刚才我们在mysql_user表中创建的用户，端口为6033

mysql -uproxysql -ppwproxysql -h127.0.0.1 -P6033

验证读写分离是否成功

• proxysql有个类似审计的功能，可以查看各类SQL的执行情况。在proxysql管理端执行：
• 从下面的hostgroup和digest_text值来看，所有的写操作都被路由至1组，读操作都被路由至2组，
• 其中1组为写组，2组为读组！

 select * from stats_mysql_query_digest;