ProxySQL簡介原理及讀寫分離應用
阿新 • • 發佈:2020-06-07
#### MySQL-ProxySQL中介軟體簡介
##### 同類型產品
- MySQL Route:是現在MySQL官方Oracle公司釋出出來的一箇中間件。
- Atlas:是由奇虎360公發的基於MySQL協議的資料庫中介軟體產品,它在MySQL官方推出的MySQL-Proxy 0.8.2版本的基礎上,修改了若干Bug,並增加了很多功能特性。目前該產品在360內部得到了廣泛應用。
- DBProxy:是由美團點評公司技術工程部DBA團隊(北京)開發維護的一個基於MySQL協議的資料中間層。它在奇虎360公司開源的Atlas基礎上,修改了部分bug,並且添加了很多特性。
- Cobar:是阿里巴巴B2B開發的關係型分散式系統,管理將近3000個MySQL例項。 在阿里經受住了考驗,後面由於作者的走開的原因cobar沒有人維護 了,阿里也開發了tddl替代cobar。
- MyCAT:是社群愛好者在阿里cobar基礎上進行二次開發,解決了cobar當時存 在的一些問題,並且加入了許多新的功能在其中。目前MyCAT社群活躍度很高,目前已經有一些公司在使用MyCAT。總體來說支援度比較高,也會一直維護下去。
> ProxySQL是使用C++語言開發的,官網文件也很齊全,以下是其特色功能點:
>
> 上面提到的MyCAT我Mysql哪一個分類文章有親測過程,有興趣小夥伴可以移步看看.
https://www.cnblogs.com/you-men/p/12838333.html
- 查詢快取
- 查詢路由
- 故障轉移
- 線上配置立刻生效無需重啟
- 應用層代理
- 跨平臺
- 高階拓展支援
- 防火牆
通過上述,我們可以看到ProxySQL可以做許多事情,已經不僅僅是純粹的MySQL讀寫分離,其實我們通過後面所述結合業務發散,ProxySQL還可以支援以下高階功能:
- 讀寫分離
- 資料庫叢集、分片
- 分庫分表
- 主從切換
- SQL審計
- 連線池 多路複用
- 負載均衡
- 查詢重寫
- 流量映象
- 自動重連
- 自動下線
`高可用架構`
![](https://img2020.cnblogs.com/blog/1871335/202006/1871335-20200607001408734-851453124.jpg)
#### ProxySQL部署配置
##### 環境清單
`list`
```python
CentOS7.3
proxysql-2.0.12-1-centos7.x86_64.rpm
mysql-5.7.23-1.el7.x86_64.rpm-bundle.tar
```
| 主機 | 作業系統 | IP地址 | 硬體/網路 |
| :---------- | :-------- | :------------ | :--------- |
| 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 |
##### 安裝Mysql
```shell
#!/usr/bin/env bash
# Author: ZhouJian
# Mail: [email protected]
# Time: 2019-9-3
# Describe: CentOS 7 Install Mysql.rpm Script
clear
echo -ne "\\033[0;33m"
cat<_/___.' >' "".
| | : '- \\'.;'\\ _ /';.'/ - ' : | |
\\ \\ '_. \\_ __\\ /__ _/ .-' / /
====='-.____'.___ \\_____/___.-'____.-'=====
'=---='
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
建議系統 CentOS7
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# PS:請儘量使用純淨的CentOS7系統,我們會在伺服器安裝Mysql5.7,
# 將mysql-5.7.23-1.el7.x86_64.rpm-bundle.tar包和指令碼放到root目錄下執行即可,密碼為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 "您無法上外網,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 < 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)
```
##### 從庫開啟Slave
```python
change master to
master_host='192.168.0.102',
master_user='slave',
master_password='ZHOUjian.200',
master_auto_position=0;
mysql> start slave;
# 檢視從庫狀態
mysql> show slave status\G;
```
##### 下載部署ProxySQL
https://github.com/sysown/proxysql/releases
```shell
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
# 本地配置檔案
# proxysql 有個配置檔案/etc/proxysql.cnf,只在第一次啟動的時候有用,
# 後續所有的配置修改都是對 SQLite 資料庫操作,並且不會更新到proxysql.cnf檔案中。 # ProxySQL 絕大部分配置都可以線上修改,配置儲存在/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 *:*
# 管理介面的埠是 6032 , 賬號密碼是 admin( 可以動態修改 ) 只能通過本地連線 , # 客戶端介面的埠是 6033 , 賬號密碼通過管理介面去設定。
```
##### 登入配置ProxySQL
`登入管理介面,配置資訊從啟動程序的配置檔案檢視`
```shell
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> '
# 不推薦跟傳統服務一樣修改/etc/proxysql.conf
# 之所以不推薦,是因為我們可以通過ProxySQL控制檯線上修改配置,無需重啟,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:預設資料庫,存放使用者驗證、路由規則等資訊。我們要做的配置都是針對這個庫的
# disk:持久化到硬碟的配置
# stats:proxysql執行抓取的統計資訊,如各命令的執行次數、查詢執行時間等
# monitor:monitor模組收集的資訊,db的健康情況、各種檢查等
# 設定SQL日誌記錄[ProxySQL]
set mysql-eventslog_filename='queries.log';
# 新增主從[ProxySQL]
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.105',3306,1,'主庫');
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.106',3306,9,'從庫');
insert into mysql_servers(hostgroup_id,hostname,port,weight,comment) values(1,'192.168.0.107',3306,1,'從庫');
# 檢視主從[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 | 主庫 |
| 1 | 192.168.0.106 | 3306 | 0 | ONLINE | 9 | 0 | 1000 | 0 | 0 | 0 | 從庫 |
| 1 | 192.168.0.107 | 3306 | 0 | ONLINE | 1 | 0 | 1000 | 0 | 0 | 0 | 從庫 |
+--------------+---------------+------+-----------+--------+--------+-------------+-----------------+-----------
# hostgroup_id:一個角色一個id,該表的主鍵是hostgroup_id+hostname+port
# hostname:db例項IP
# port:db例項埠
# weight:權重,如果有多個相同角色的例項,會優先選擇權重高的
# status:狀態
# -ONLINE 正常
# -SHUNNED 臨時被剔除
# -OFFLINE_SOFT 軟離線狀態,不再接受新的連線,已建立的連線會等待
# -OFFLINE_HARD 離線,不接收新連線, 已建立的連線也會強制斷開(宕機或者網路不可用)
# max_connections:最大連線數
# max_replication_lag:允許的最大延遲
# 建立主從賬號[MySQL]
create user 'proxysql'@'%' identified by 'ZHOUjian.21';
mysql> grant all privileges on *.* to 'proxysql'@'%' with grant option;
# 新增主從賬號[ProxySQL]
insert into mysql_users(username,password,default_hostgroup,transaction_persistent)values('proxysql','ZHOUjian.21',1,1);
# 檢視主從賬號
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:
# 建立監控賬號[MySQL]
CREATE USER 'monitor'@'%' IDENTIFIED BY 'ZHOUjian.21';
GRANT SELECT ON *.* TO 'monitor'@'%' WITH GRANT OPTION;
# 新增監控賬號[ProxySQL]
set mysql-monitor_username='monitor';
set mysql-monitor_password='ZHOUjian.21';
# 檢視監控賬號[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 |
+--------------------------------------------------------------+----------------+
# 也可以像下面這樣快速定位
select @@mysql-monitor_username;
+--------------------------+
| @@mysql-monitor_username |
+--------------------------+
| monitor |
+--------------------------+
select @@mysql-monitor_password;
+--------------------------+
| @@mysql-monitor_password |
+--------------------------+
| ZHOUjian.21 |
+--------------------------+
```
`檢測監控`
```python
# 檢測上述配置是否正確:connect_error為NULL則正確
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) |
```
##### 配置讀寫對映[ProxySQL]
> 這裡配置主從自動切換: 互為主從,自動切換,保證高可用
`新增讀寫分離的路由規則`
- 將select語句全部路由至hostgroup_id=2的組(也就是讀組)
- 但是select * from tb for update這樣的語句是修改資料的,所以需要單獨定義,將它路由至hostgroup_id=1的組(也就是寫組)
- 其他沒有被規則匹配到的組將會被路由至使用者預設的組(mysql_users表中的default_hostgroup)
```python
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 |
+---------+--------+----------------------+-----------------------+-------+
# 將剛才我們修改的資料載入至RUNTIME中(參考ProxySQL的多層配置結構):
# load進runtime,使配置生效
load mysql query rules to runtime;
load admin variables to runtime;
# save到磁碟(/var/lib/proxysql/proxysql.db)中,永久儲存配置
save mysql query rules to disk;
save admin variables to disk;
```
#### 測試讀寫分離
##### 連結proxysql客戶端
> 登入使用者是剛才我們在mysql_user表中建立的使用者,埠為6033
```mysql
mysql -uproxysql -ppwproxysql -h127.0.0.1 -P6033
```
##### 驗證讀寫分離是否成功
- proxysql有個類似審計的功能,可以檢視各類SQL的執行情況。在proxysql管理端執行:
- 從下面的hostgroup和digest_text值來看,所有的寫操作都被路由至1組,讀操作都被路由至2組,
- 其中1組為寫組,2組為讀組!
```mysql
select * from stats_mysql_query_dige