Providing a suitable High Availability (HA) solution for each database system is one of the challenging tasks for a DBA and here we have to answer some questions like the following ones:

1. What is the cost for that HA solution?
2. Is it required to change the system structure or the DB design to use that HA solution?
3. Is it complicate to understand, use or maintain ?

Choosing the suitable HA solution for each system will depend on the answers of such questions …
In this post, I’m going to write about MySQL Master High Availability MHA as a nice tool which provides HA for MySQL by performing automatic fail-over or fast online master switching with almost no downtime!

Before going through more details about MHA, let’s first answer the previous questions:

1. MHA is a free opensource tool, no cost to use it in your system and even no additional servers are required.
2. No system changes or DB redesign are required to use MHA, keep your system as it is and just use the tool! (Assuming that MySQL replication is already being used).
3. MHA is easy to implement and its usage is simple.

Continue reading →