Repmon

Repmon is a simple database replication monitoring tool. Repmon will send notifications based on database replication failure. Repmon also optionally support HTTP healthchecks for database replication.

Supported Databases

• MySQL 5.5 (possibly other MySQL versions but untested)

Supported Notifications

• Email

HTTP Healthcheck

Repmon can optionally listen for HTTP health probes at /healthcheck. It will return a 200 status code if replication is running and a 503 otherwise.

How does it work?

1. Download the latest release.
2. Create a YAML configuration file
3. Run it repmon -conf repmon.yaml

Configuration file

The YAML file defines repmon's operation.

Full config example

log_path: /var/log/repmon.log
log_level: error
frequency: 1h
http:
  addr: 0.0.0.0
  port: 4040
mysql:
  host: 127.0.0.1
  port: 3306
  user: user
  pass: pass
email:
  host: mail.me.com
  port: 587
  user: me
  pass: pass
  starttls: true
  ssl: false
  subject: Database Replication Failure
  from: me@me.com
  to:
    - you@me.com

Global Options

log_path - File on disk where repmon logs will be stored. Defaults to /var/log/repmon.log.

log_level - Sets the log level. Valid levels are: panic, fatal, trace, debug, warn, info, and error. Defaults to error.

frequency - How often repmon will check the database to ensure replication is running. Defaults to 1h.

HTTP

addr - The listening address for the HTTP server. Default to 127.0.0.1

port - The listening port for the HTTP server. Default to 4040

MySQL

host - The hostname or IP of the MySQL server.

port - The port of the MySQL server.

user - The username used to authenticate.

pass - The password used to authenticate.

socket_path - Connect to the MySQL database through a socket file rather than a port.

Email

host - The hostname or IP of the SMTP server.

port - The port of the SMTP server.

user - The username used to authenticate.

pass - The password used to authenticate.

start_tls - StartTLS enables TLS security. If both StartTLS and SSL are true then StartTLS will be used.

insecure_skip_verify - When using TLS skip verifying the server's certificate chain and host name.

ssl - SSL enables SSL security. If both StartTLS and SSL are true then StartTLS will be used.

from - The email address the email will be sent from.

to - An array of email addresses for which emails will be sent.

subject - An optional subject field for replication failure emails.

Flags

-conf - Path to the repmon configuration file

-debug - Log to STDOUT

HTTP Health Checks

The optional HTTP server creates two endpoints.

/live - A liveness check that always returns 200.

/health - A health check that returns 200 if the if there are no replication errors and 503 otherwise.

Road Map

• Docker Image
• Systemd service file
• Create rpm
• Create deb
• Support for more databases
• Support for more notifiers