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|Does your application need CDP?|
IS IT HIGH TRANSACTION?
DOES IT FACE recovery point objective or recovery time objective pressure?
IS RECOVERY a complex process?
If you answered "YES" to any of these questions, you should consider evaluating continuous data protection (CDP) to enhance your application recovery processes.
Blocks or files?
In the block approach, all data entering into the CDP application is stored in much the same way a traditional volume manager writes data. Whether that data capture is taking place on the host or in a network device, any data state for the application will be recovered. Because it's free of file-level semantics, block-level data capture works across all data types: structured, semi-structured and unstructured content.
When it comes to recovering data, a block-level approach creates "recovery objects" determined by the application requesting it: database tables or rows, e-mail items, mailboxes, etc. However, block-level approaches don't automatically recover file-level information because this requires integration with a file system. For database application recovery, block-level data capture is the preferred method employed by CDP vendors today.
File-level CDP products are typically built with extended functionality for particular applications, such as SQL Server or Exchange. By recovering data directly to the file level, the CDP product can achieve a much tighter integration with a top-level application because no conversion is required between the physical and logical layers, as would be the case in a block-based approach. Users who want to implement CDP across multiple platforms will have to use a CDP application based on the block approach.
Today, approaches to application recovery vary widely among CDP products, as do the degrees to which these products integrate with supported applications. Within the next 18 months, many of these architectural differences will recede. Multiplatform vendors will bring to market a range of application-specific modules and integrated tools, deepening support across key applications. At the same time, application-specific CDP vendors will supply more automation capabilities and direct integration with business processes.
Looking further out, over the next three years, CDP technologies will likely become an integrated part of an emerging discipline of application recovery. Ultimately, top-level applications riding above databases (such as ERP, CRM, Web-based services, etc.) will be able to execute a range of self-healing or self-recovering functions without direct administrative interaction from the storage layer. There will also come a time when the application will be able to identify a corruption event and correct it without any intervention.
You can expect the major application software vendors, such as Microsoft Corp., Oracle Corp. and SAP AG, to expose APIs in their applications or provide tool suites that enable CDP-driven recovery. CDP technologies, working in direct conjunction with the app, will chart the future of information recovery.
This was first published in November 2005