pxc-checker

Percona/MySQL XtraDB Cluster Checker

This project is percona-clustercheck like checker rewrited to Golang. Program to make a proxy (ie HAProxy) capable of monitoring Percona XtraDB Cluster nodes properly.

Usage

Basic Haproxy config:

listen pxc
  bind 127.0.0.1:3306
  balance leastconn
  option httpchk HEAD /
  mode tcp
  default-server inter 500 rise 5 fall 5
    server node1 1.2.3.4:3306 check port 9200
    server node2 1.2.3.5:3306 check port 9200
    server node3 1.2.3.6:3306 check port 9200 backup

Setup

1. Create MySQL user:

   create user 'pxc_checker'@'localhost' IDENTIFIED BY 'YourStrongPassword'; GRANT PROCESS ON *.* TO 'pxc_checker'@'localhost';
   

2. Get program binary. You can choose one of the following methods:
   • Build it from source code with:

     go get
     go build -o pxc-checker ./...
     

   • Download latest compiled binary from Releases page.
3. Copy binary to /usr/bin/pxc-checker
4. Copy systemd unit from systemd/pxc-check@.service to /etc/systemd/system/pxc-checker@.service
5. Copy example config from config/example.conf to /etc/pxc/checker/cluster.conf and modify it.
6. Enable and start unit with command: systemctl enable --now pxc-checker@cluster
7. Check node status with command: curl http://127.0.0.1:9200

Configuration file options

You can override any of the following values in configuration file:

• WEB_LISTEN: Web server listening interface and port in format {IPADDR}:{PORT} or :PORT for all interfaces. Default: :9200
• WEB_READ_TIMEOUT: Web server request read timeout in milliseconds. Default: 30000
• WEB_WRITE_TIMEOUT: Web server request write timeout in milliseconds. Default: 30000
• CHECK_RO_ENABLED: Mark 'read_only' node as available. Default: false
• CHECK_FORCE_ENABLED: Ignoring the status of the checks and always marking the node as available. Default: false
• CHECK_DONORS_ENABLED: Mark donors nodes as available. Default: false
• CHECK_INTERVAL: Mysql checks interval in milliseconds. Default: 500
• CHECK_FAIL_TIMEOUT: Mark the node inaccessible if for the specified time (in milliseconds) there were no successful checks. Default: 3000
• MYSQL_HOST: MySQL host address. Default: 127.0.0.1
• MYSQL_PORT: MySQL port. Default: 3306
• MYSQL_USER: MySQL username. Default: pxc_checker
• MYSQL_PASS: Mysql password. Default: no password