How do I identify what data to replicate and what data to simply backup?
It goes back again to the value of the data to your organization -- or the impact of losing access to this data.
Typically, from a business continuity perspective, the best way to establish this
is through what we call a "business impact analysis
," which really measures the impact of an outage on your revenue stream or your organization from a public perception point of view. You need to start from the business processes and look at what applications these business processes depend on -- and then you move down the chain. Once you've identified the application and the dependency, you can start looking at the data that these applications use, and categorize the data
based on the business processes that use that data and the importance of those business processes to the organization from a revenue perspective.
We always have to make the distinction between qualitative and quantitative impact. Quantitative impact is fairly easy to measure; it's dollar value. The qualitative impact is really from a public perception -- loss of confidence in your company or your brand. For example, if you can't do banking for a few hours online, the bank could lose a few customers. So, the impact of an outage is not necessarily measured in dollars, but eventually will translate into dollars. That's the qualitative impact. Really that's what drives the value of data, and in the end, helps you identify and categorize the data to decide what you should replicate. This is also where you can start moving into storage tiers
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This was first published in August 2006