Gonarch HA community edition

Deploy a robust MySQL high availability solution utilizing Gonarch HA, a versatile open-source tool that integrates proxy, load balancing, automatic failover, and replication management functionalities into a cohesive package.

Documentation: https://github.com/raa82/gonarch_ha_ce/wiki

Creator LinkedIn profile: https://www.linkedin.com/in/ralvarezaragon/

Support

You can reach me either via LinkedIn (I'm pretty active there) or via email at ralvarez@gonarch.tech

Features

• Auto failover. Gonarch HA detects if the primary goes down or loses connectivity and initiates the promotion of a healthy replica based on the promotion rules that you define.
• Promotion rules. It allows you to select replicas for promotion based on a given criteria, so you can prioritize data consistency or availability.
• Traffic balance. Read traffic can be distributed only to replicas or to the whole cluster.
• Topology discovery. New nodes are automatically attached and managed by GHA.
• Backup mode. Flag any replica as a backup, and it will stop serving traffic. You can set it back once the backup is finished and keep the replica useful for the rest of the day.
• Integration. Every single communication with GHA happens through the API. This makes it easy to control any aspect or fetch any information from your application.

Next steps

• Chained replication management
• Multi data center recognition

Install

Using installer

Just download the latest release tar file and run install.sh but keep in mind that the script only runs in Ubuntu for now.

Without installer

The whole installation script can be done manually in case you are not in Ubuntu. As ROOT:

• Clone this repo
• Install sqlite3, haproxy and socat in your OS (packages names may vary)
• Create the folder in /opt/gonarch, /run/haproxy and /var/log/gonarch
• Move gonarch.conf to /etc/

  mv resources/gonarch.conf.template /etc/gonarch.conf

• Edit /etc/gonarch.confg and change this

  workspace:
  name: Choose a workspace name (this has no real impact so far just pick up anything you want)
  ip: This host IP
  env: Production

• Move resources/haproxy_template.j2 and check_status.sh to /opt/gonarch
• Download the latest release package and uncompress it
• Move the bin/* content to /opt/gonarch
• Create the sqlite backend DB

  sqlite3 /opt/gonarch/backend.db < resources/backend_table_def.sql

• Create gonarch user at OS level and change ownership to it for these files/folders:

  chown gonarch:gonarch /etc/gonarch.conf
  chown gonarch:gonarch /etc/haproxy/haproxy.cfg
  chown -R gonarch:gonarch /opt/gonarch
  chown -R gonarch:gonarch /var/log/gonarch

• Move systemd files

  cp resources/gonarch-check.service /etc/systemd/system/
  cp resources/gonarch-core.service /etc/systemd/system/
  cp resources/gonarch-api.service /etc/systemd/system/

• Reload systemctl daemons

  systemctl daemon-reload

• Start Gonarch HA services

  systemctl restart haproxy
  systemctl start gonarch-check
  systemctl start gonarch-core
  systemctl start gonarch-api

Now Gonarch HA is installed and ready to be used regardless of the Linux distro.

Python dependencies

Just in case you want to use the py files instead the binaries ensure the following dependencies are installed:

sqlalchemy==1.4.44
flask
flask_cors
waitress
requests
pyyaml
tabulate
mysqlclient (This library usually requires some extra packages from your OS but it depends on the flavour)

NOTE: Your OS could have a firewall (UFW, SeLinux) in place that block multiple modules. Ensure you have whitelisted these systemd processes.