A high availability DB system is made up of three MySQL instances: a primary instance, and two secondary instances. All data that you write to the primary instance is copied to the secondary instances. A high availability DB system guarantees if one instance fails, another takes over, with zero data loss and minimal downtime.

• Overview of High Availability
• Prerequisites
• Enabling or Disabling High Availability
• Failover
• Switchover
• Limitations
• Billing