Prometheus 监控插件mysqld exporter

要增加授权

mysql> GRANT PROCESS, REPLICATION CLIENT, SELECT ON *.* TO 'exporter'@'localhost' IDENTIFIED BY 'exporter123' WITH MAX_USER_CONNECTIONS 3;
mysql> flush privileges;

安装mysqld_exporter

wget https://github.com/prometheus/mysqld_exporter/releases/download/v0.12.1/mysqld_exporter-0.12.1.linux-amd64.tar.gz
tar xzvf  mysqld_exporter-0.12.1.linux-amd64.tar.gz
mv mysqld_exporter-0.12.1.linux-amd64.tar.gz  mysqld_exporter
chown -R root:root /usr/local/prometheus/mysqld_exporter/mysqld_exporter
chmod 755 /usr/local/prometheus/mysqld_exporter/mysqld_exporter

修改启动参数

启动参数参考 https://github.com/prometheus/mysqld_exporter

vim /usr/lib/systemd/system/mysqld_exporter.service
[Unit]
Description=mysqld_exporter
After=network.target
[Service]
Type=simple
User=mysql
Environment=DATA_SOURCE_NAME=exporter:exporter123@(localhost:3306)/
ExecStart=/usr/local/prometheus/mysqld_exporter/mysqld_exporter --web.listen-address=0.0.0.0:9104 
  --config.my-cnf /etc/my.cnf \
  --collect.slave_status \
  --collect.slave_hosts \
  --log.level=error \
  --collect.info_schema.processlist \
  --collect.info_schema.innodb_metrics \
  --collect.info_schema.innodb_tablespaces \
  --collect.info_schema.innodb_cmp \
  --collect.info_schema.innodb_cmpmem 
Restart=on-failure
[Install]
WantedBy=multi-user.targe

[Unit]
Description=mysqld_exporter

[Service]
Type=simple
Restart=on-failure
ExecStart=/usr/local/mysqld_exporter/mysqld_exporter --config.my-cnf=/usr/local/mysqld_exporter/my.cnf 

[Install]
WantedBy=multi-user.target

启动exporter

chown -R root:root /usr/lib/systemd/system/mysqld_exporter.service
chmod 644 /usr/lib/systemd/system/mysqld_exporter.service
systemctl daemon-reload
systemctl enable mysqld_exporter.service
systemctl start mysqld_exporter.service

访问localhost:9104/metrics可以看到mysql的指标

修改prometheus配置文件

scrape_configs下面添加

vim /usr/local/prometheus/prometheus.yml
scrape_configs:
  - job_name: 'mysql'
    static_configs:
      - targets: ['localhost:9104']

设置报警规则

可参考示例：https://github.com/prometheus/mysqld_exporter/blob/master/example.rules

groups:
- name: GaleraAlerts
  rules:
  - alert: MySQLReplicationNotRunning
    expr: mysql_slave_status_slave_io_running == 0 or mysql_slave_status_slave_sql_running
      == 0
    for: 2m
    labels:
      severity: critical
    annotations:
      description: Slave replication (IO or SQL) has been down for more than 2 minutes.
      summary: Slave replication is not running