We cannot stress the importance of this section strongly enough. Some may consider an entire extra data center as optional due to the cost. It is not. Others may think a total of three servers for every primary system is too much maintenance overhead. Again, it is not. The price of a few servers must be weighed against the future of the company itself; it is the cost of admission into the world of high availability.
By the time we begin utilizing failover nodes, or any replicas in a separate data center, the damage has already been done. In the absence of these resources, a database crash can result in hours or even days of unavailability depending on the size of our database, exponentially compounding the effects of the original ...
