mysqld_exporter是Prometheus用于监控MySQL指标的一个导出器，支持对MySQL 5.5以上进行监控。用来抓取mysql的相关信息，下面是mysqld_exporter 安装的相关信息

环境： 192.168.31.40 MariaDB-5.5.68 mysqld_exporter_0.12.1

一、下载mysqld_exporter 并安装

官方网址：
https://prometheus.io/download/

选择对应的版本下载

[root@node-1 ~]# wget https://github.com/prometheus/mysqld_exporter/releases/download/v0.12.1/mysqld_exporter-0.12.1.linux-amd64.tar.gz

#解压 ，移动到/usr/local 路径下 并从命名为 mysqld_exporter

[root@node-1 ~]# tar -xf mysqld_exporter-0.12.1.linux-amd64.tar.gz

[root@node-1 ~]# mv mysqld_exporter-0.12.1.linux-amd64 /usr/local/mysqld_exporter

二、登陆数据库，创建授权账户

[root@node-1 ~]# mysql -uroot -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 278
Server version: 5.5.68-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> grant PROCESS, REPLICATION CLIENT, SELECT on *.* to 'exporter'@'localhost' identified by 'fxkjnj';
MariaDB [(none)]> flush privileges;

#注意： 这里我只授权了本机登陆，因为 mysqld_exporter 也安装在数据库这台主机上

#退出验证，使用exporter 用户登陆数据库

 [root@node-1 ~]# mysql -uroot -p'fxkjnj'
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 286
Server version: 5.5.68-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> show grants;
+----------------------------------------------------------------------------------------------------------------------------------------+
| Grants for root@localhost                                                                                                              |
+----------------------------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' IDENTIFIED BY PASSWORD '*A88C2B91E04CF458B1EFF3228824DEA7CE4ABA22' WITH GRANT OPTION |
| GRANT PROXY ON ''@'' TO 'root'@'localhost' WITH GRANT OPTION                                                                           |
+----------------------------------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

MariaDB [(none)]> 

三、创建mysqld_exporter 的配置文件 my.cnf

[root@node-1 mysqld_exporter]# vim /usr/local/mysqld_exporter/my.cnf

[client]

host=192.168.31.40

port=3306

user=exporter

password=fxkjnj

四、创建mysql_exporter 启动文件，使用systemd 管理

[root@node-1 mysqld_exporter]# vim /etc/systemd/system/mysqld_exporter.service 
[Unit]
Description=mysqld_exporter
Documentation=mysqld_exporter-doc
 
[Service]
ExecStart=/usr/local/mysqld_exporter/mysqld_exporter --config.my-cnf=/usr/local/mysqld_exporter/my.cnf
 
[Install]
WantedBy=multi-user.target

#初始化并启动mysqld_exporter

[root@node-1 mysqld_exporter]# systemctl daemon-reload

[root@node-1 mysqld_exporter]# systemctl start mysqld_exporter.service

#查看进程及端口

[root@node-1 ~]# ps -ef | grep mysqld_exporter | grep -v grep

root 60884 1 0 16:55 ? 00:00:02 /usr/local/mysqld_exporter/mysqld_exporter --config.my-cnf=/usr/local/mysqld_exporter/my.cnf

[root@node-1 ~]# netstat -ntlup | grep mysqld_export

tcp6 0 0 :::9104 :::* LISTEN 60884/mysqld_export

五、修改prometheus 配置文件 指定 mysqld_exporter 采集器地址

[root@prometheus ~]#vim /etc/prometheus/prometheus.yml

[root@prometheus ~]#vim /etc/prometheus/prometheus.yml
..............

scrape_configs:
  - job_name: 'prometheus'
    static_configs:
    - targets: ['192.168.31.250:9090']


  - job_name: 'mysql'
    static_configs:
    - targets: ['192.168.31.40:9104']

..............

#热加载prometheus

[root@prometheus ~]# ps -ef | grep prometheus | grep -v grep | awk '{print $2}' | xargs kill -HUP

#登陆到prometheus 控制台，可以在status/targets 里看到 mysqld_exporter 采集器相关信息

点击
http://192.168.31.40:9104/metrics 可以看到相关数据

六、使用grafana 展示 mysqld_exporter 采集器采集的数据

PS： grafana 添加 prometheus 数据源 过程 省略。。。。。。。。。。

为了最终的效果，我们使用 Grafana 官网小伙伴提供的dashboard 来展示数据

模板地址：
https://grafana.com/grafana/dashboards/7362 ID： 7362

点击 Download JSON , 下载完后 登陆Grafana ，默认地址 http://IP:3000

找到左侧 + 号，import 导入刚刚下载的json 文件

选择好数据源

稍等片刻，就可以看到 最终的效果

本篇只涉及到 使用mysqld_exporter 收集mysql 数据并展示 ，并没有写到 触发器的配置告警，这个等后面再更新