temoto / mysql-leader-kuska

Mysql leader (master) election using consul lock

What

Set of configs and scripts to keep a single mysql server from a set of replicas in write mode.

If you are determined to use ring replication, this may help to automate writable master election.

Requirements

• Any Mysql compatible server (maria, percona, etc)
• Consul https://www.consul.io/
• 2 mysql servers in ring replication
• application (mysql client) is configured without persistent connections or very short lived connections (under 2sec)
• application does not cache DNS responses

Installation

• enable script checks in consul https://www.consul.io/docs/agent/options.html#_enable_script_checks
• copy entire directory structure to all mysql server machines
• change clustername in /etc/mysql-leader.env and /etc/consul.d/mysql-leader.hcl
• change mysql_replication_{user,password} in /etc/mysql-leader.env
• tune timeouts in systemd/mysql-leader.service, consul.d/mysql-leader.hcl to your taste
• restart mysql.service
• configure application to go to mysql-clustername-{read,write}.service.consul accordingly for reads and writes

Contact

[e-mail]