Integrating replication into the application is a study in the art of the possible. The ideal solution for the business unit application will often be remote replication over long distances with zero loss of data and instant recovery. Physics and dollars will usually dictate compromise.
Remote replication is about recovering from a disaster at the primary site. No application is an island; the first priority is to understand the application and its ecosystem of support application. The next stage is to understand the business impact of an outage and the business impact of data loss on this application and its ecosystem. This business impact has to be expressed in dollars and the expected loss (probability of loss x loss) calculated. Then the impact on different solutions on loss and expected loss and recovery time has to be estimated, along with the cost of those alternatives.
Action Item: Integrating replication into an application requires solid communication between the business and IT and a rich toolkit of alternative approaches, including host based replication, array-based asynchronous and synchronous replication, and different communication methods. Calculation and communication are the staples of such projects.
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