In this three-part blog series, we introduced a High Availability (HA) Framework for MySQL hosting in Part I, and discussed the details of MySQL semisynchronous replication in Part II. Now in Part III, we review how the framework handles some of the important MySQL failure scenarios and recovers to ensure high availability.

MySQL Failure Scenarios Scenario 1 – Master MySQL Goes Down

• The Corosync and Pacemaker framework detects that the master MySQL is no longer available. Pacemaker demotes the master resource and tries …

I have used many tools starting with MMM to be able to manage MySQL replication clusters. Some of the tools need more tools and complex HA solutions such as Pacemaker and Corosync, or Zookeeper. While other tools do not do the failover well which leaves the slaves in an inconsistent state, MMM would be an example. And I must say that of all the tools I love MySQL Master HA (MHA) the most. MHA is a great tool to manage MySQL replication clusters for the purpose of HA. The most important thing about MHA is that it tries to take all the necessary steps to do a MySQL master failover in a way that provides as much data consistency as possible. The slave promotion also tends to be very quick, on average I have seen it take 10 to 15 seconds. It is also very easy to deploy unlike some of the other complex HA solutions. I would highly recommend reading about the architecture of MHA on its wiki: https://code.google.com/p/mysql-master-ha/wiki/Architecture Why …

With all of the new news coming out right now, it can be easy to miss or overlook some of the new features.

While there’s been a lot of talk about MySQL 5.6 Replication, I specifically wanted to mention the new ‘mysqlfailover’ and ‘mysqlrpladmin’ utilities.

These are two new MySQL replication utilities (results of the new Global Transaction Identifiers (GTIDs) in MySQL 5.6).

Let me quote the MySQL 5.6 Replication article for both of these utilities:

mysqlfailover

“Provides continuous monitoring of the replication topology, enabling failover to a slave in the event of an outage on the master.

The default behavior is to promote the most up-to-date slave, based on …