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Business need: Transactional data requires fast, 100% accurate writes and reads either to support customers or meet the requirements of high-speed applications. One common example is online retail. Numerous surveys have shown that even relatively short delays in response to customer actions can result in lost sales, making high performance storage essential. Storage solution: Generally latest-generation, high-speed disk systems are used. These systems carry a premium price, but this cost is justified because slower performance systems would directly impact the business. However, even as disk becomes faster, solid state storage prices are decreasing and availability is increasing. As this trend continues solid state “drives” will find their way into the Tier 1 systems of increasing numbers of organizations.
Business Need: This tier supports many major business applications from email to ERP. It must securely store the majority of active business data, where subsecond response is not a requirement but reasonably fast response still is needed. Email systems, which generate large amounts of data, are a prime example. While users can tolerate slightly slower response times that is required for transactional systems, they are quickly frustrated by consistently slow response. Solution: Tier 2 technology is always a balance between cost and performance. The latest entrant in this tier is XIV, now part of IBM, which offers large storage volumes and good-enough performance for Tier 2 at a very low price. The one catch is that to accomplish that, XIV systems come in two standard sizes. Multiple systems can be chained together to handle larger amounts of data, but the size minimum can lock out the lower end of the SMEs.
Business Need: As data ages, reads drop off rapidly. However, that data often is still used for trend analysis and complex decision support. For instance, financial data needs to be kept accessible at least until the end of the fiscal/tax year. However, it does not need to stay on more expensive Tier 1 and Tier 2 systems. Similarly emails more than a couple of weeks old are seldom accessed, but the business may still find it desirable to keep them on easily accessible systems. Solution: Tier 3 technologies can have two different characteristics. Much of the data in Tier 3 is really semi-active. MAID technology is a good choice for that data. However, it also handles data that supports decision support analysis. Businesses that do a lot of complex analysis of historical business data might consider a storage system designed to support complex queries such as the Sybase IQ series of column-based systems designed specifically to support complex analysis as a Tier 3B solution for that data.
Business need: Compliance requirements today are driving a tremendous explosion in storage for historical data. In the United States, for instance, state and federal civil courts often require companies to produce large amounts of historic emails, sometimes going back years, in civil torts. Often businesses rely on backup tapes to recover this data. However, backup tape procedures were never designed to preserve data going back several years. Tapes are lost, reused, or may have deteriorated. The technologies to read them may no longer be available. J.P. Morgan and other companies have learned the inadequacies of using backup tapes to archive old data to their cost in some highly publicized court cases. Backup tapes have another problem when used for archiving. They contain a snapshot of the entire corporate data population across all applications at a particular moment. This means that when an ITO is responding to a court request, for instance, for emails between specific people between specific dates that may span several years, it has to resurrect and search a large number of tapes containing extraneous data such as corporate financials and HR records for individual emails and reconstruct them into a chronological file.
Businesses need a better system for long-term storage of historical data. This is as much an issue of procedure as technology. Rather than backup tapes, it needs tapes or other media containing archives of a specific data type – for instance all corporate email week by week. These need to be formally archived in an organized fashion with full records of exactly what is on each tape or other medium, where it is, what technology is needed to recover it, and when it needs to be migrated to a new physical medium to ensure that data integrity is maintained. Migration procedures need to be established to ensure that each tape is replaced before it reaches its end of life, and old tape technologies that are being replaced in the data center need to be preserved in the archive to read old tapes.
Tier The solution storage Problems:
Tier 4 will contain very large amounts of data, but on the other hand no one expects this data to be instantly available. Courts, for instance, routinely give organizations two-to-four weeks to produce documents in discovery. For this reason, tape is by far the most cost-effective physical medium for much of this data. If the old data is needed either to respond to a court discovery or to support internal analysis, typically users can tolerate the time needed to mount the relevant archive tapes. Removable disks may also be considered. However, they tend to be more expensive and delicate than tape.
A multitiered storage system with automated data movement provides the best solution for managing the data explosion IT is experiencing. While not all companies need five tiers, they do all need at least three, including a data archive. Organizations that do not archive their data take a large risk if they are ever involved in a civil or criminal action and are required to produce historic documents. Overall, active tiering provides the best solution for supporting service level agreements at the minimal cost and with highest efficiency.