This is a guest post from Igor Shevtsov, a MySQL DBA based in Twickenham, UK. Igor has had the opportunity to deploy and manage different types of high availability MySQL solutions, and we invited him to share his experience. Igor can be contacted by email or LinkedIn.
Migrating from MMM to MariaDB Galera Multi-Master Replication
Agenda:
- MySQL HA with MMM
- Why MMM did not work for us
- Migration requirements
- Migration
MySQL HA with MMM
Firstly I would like to say few words about our original MMM (Multi Master Management) MySQL setup and some reasons why we decided to start looking for another MySQL HA solution.
We had 2 Data Centres with Active master1 in DC1 and passive master2 and Management node in DC2, both masters were running MariaDB 5.5 server. The clients were unevenly distributed across both DC's. DC's were connected by a VPN that wasn't 100% reliable and that occasionally failed.
The simplicity of MMM setup and management as well as speed of failover let us to believe that it was a good choice for MySQL HA. As it usually happens, we did not have much time to test it properly and we quickly realized its limitations after the VPN failed. And of course, it had to fail at night :-(