Use Prometheus and Grafana to monitor MySQL server performance.
Use two exporter s:
Node? Exporter: server system data collection
mysqld_exporter: MySQL server data collection
Monitoring architecture:

• Prometheus installation configuration
  Installation mode binary installation, see here for details CentOS7 deployment Prometheus
  Version: current latest prometheus-2.18.1
  Modify the Prometheus configuration file prometheus.yml to mainly configure the scratch configuration item.

  scrape_configs:
  # The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
  - job_name: 'prometheus'
  # metrics_path defaults to '/metrics'
  # scheme defaults to 'http'.
  static_configs:
  - targets: ['10.20.1.63:9090']
  - job_name: 'local_node'
  static_configs:
    - targets: ['10.20.1.63:9100']
      labels:
        instance: prometheus_node
  - job_name: 'mysql01'
  static_configs:
    - targets: ['10.20.10.18:9104']
      labels:
        instance: db1
  - job_name: 'mysql02'
  static_configs:
    - targets: ['10.20.10.19:9104']
      labels:
        instance: db2

• Install exporter
  Download and install node and mysqld exporters. Download https://prometheus.io/download from the official website/
  The versions are node-0.18.1 and mysqld-0.12.1, respectively.
  1) Install node? Exporter

  wget https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz
  mkdir -p /opt/prometheus
  tar xzvf node_exporter-0.18.1.linux-amd64.tar.gz 
  mv node_exporter-0.18.1.linux-amd64 /opt/prometheus/
  ln -s /opt/prometheus/node_exporter-0.18.1.linux-amd64/ /opt/prometheus/node_exporter

  Add system service startup
  First, create a prometheus user to start the node [exporter].

  useradd  -s /sbin/nologin -M prometheus

  vim /usr/lib/systemd/system/node_exporter.service

  [Unit]
  Description=node_exporter
  Documentation=https://prometheus.io/
  After=network.target
  [Service]
  Type=simple
  User=prometheus
  ExecStart=/opt/prometheus/node_exporter/node_exporter 
  Restart=on-failure
  [Install]
  WantedBy=multi-user.target

  Start the node exporter service

  systemctl status node_exporter.service

  2) Install mysqld? Exporter

  wget https://github.com/prometheus/mysqld_exporter/releases/download/v0.12.1/mysqld_exporter-0.12.1.linux-amd64.tar.gz
  mkdir -p /opt/prometheus
  mv /usr/local/mysqld_exporter-0.12.1.linux-amd64/ /opt/prometheus/
  ln -s /opt/prometheus/mysqld_exporter-0.12.1.linux-amd64/ /opt/prometheus/mysqld_exporter
  chown -R prometheus:prometheus /opt/prometheus/

  Add system service startup
  First, create the prometheus user to start mysqld_exporter.

  useradd  -s /sbin/nologin -M prometheus

  vim /usr/lib/systemd/system/mysqld_exporter.service

  [Unit]
  Description=node_exporter
  Documentation=https://prometheus.io/
  After=network.target
  [Service]
  Type=simple
  User=prometheus
  ExecStart=/opt/prometheus/mysqld_exporter/mysqld_exporter --config.my-cnf=/opt/prometheus/mysqld_exporter/.my.cnf
  Restart=on-failure
  [Install]
  WantedBy=multi-user.target

  Startup parameters: - config.my-cnf=".my.cnf" ා specify the configuration file
  Start mysqld? Exporter service

  systemctl status mysqld_exporter.service

  Mysqld ﹣ exporter needs to connect to MySQL, so it needs the permission of Mysql to create the user of MySQL ﹣ exporter and give the required permission.

  mysql> GRANT REPLICATION CLIENT,PROCESS ON *.* TO 'mysql_exporter'@'localhost' identified by 'xxxxxx';
  mysql> GRANT SELECT ON *.* TO 'mysql_exporter'@'localhost';

  Create the. my.cnf file and restart the mysqld? Exporter service.
  vim /opt/prometheus/mysqld_exporter/.my.cnf

  [client]
  user=mysql_exporter
  password=xxxxxx

• Prometheus monitoring
  Go back to Prometheus and check the status - > targets page on the Web. You can see that the State of the Target is UP, indicating that the exporter has collected the monitoring data.
  
  Prometheus monitoring uses promSQL to view mysql monitoring information, such as mysql global status connections.
  
  However, the graphics provided by Prometheus are not powerful enough, so we use Grafana as the Dashboard of Prometheus.
• Configure Grafana
  Through the default 3000 port of grafana, visit the website of grafana and add data source
  
  Here, select the Prometheus data source, where the URL fills in the Prometheus address, and other items remain the default. Click Save & test to add it as follows.
  
  Granfina imports Mysql monitoring chart. recommend https://grafana.com/grafana/dashboards/7362 Monitor the template and export Download JSON.
  Granfina enters create - > import to import Dashboards.
  
  The monitoring items are very detailed, and the final presentation is as follows: