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|Which WORM-- Disk, Tape or Optical?|
Planning for Obsolescence
A major concern for any WORM media is the ability to access the data on the media in which it's stored. Storing data on media with a shelf life of 15, 30 or 50 years sounds prudent, but the more important issue is making sure the hardware still exists to read the media after an extended number of years.
Rather than trying to keep tape cartridges forever, plan on making all cartridges obsolete after five years and make sure no cartridge remains past 10 years. As tape cartridges start approaching five years, migrate the data on those media that have a retention period of longer than 10 years to current, larger capacity tapes. You will likely be able to reduce the number of tapes in your environment, keep your environment manageable for the longer term and avoid any long-term liabilities.
WORM tape policies
Storing data on WORM tape--which has a life expectancy of 15 to 30 years--could incur potential legal liabilities later on if an organization can't identify and destroy the data on those tapes that has exceeded its required retention period. A number of organizations can tell horror stories about having to spend money to recover decades-old data from tape that should have been destroyed years ago. Without a tool to track and report on what media the data resides on and when to get rid of it, WORM tape can exacerbate this risk because it can only be destroyed, not reformatted.
In most cases, storage managers can use their existing backup software to track the age of the data on WORM tape cartridges. Of course, the backup will need some level of integration with the applications. For example, add-on options such as ApplicationXtender and EmailXtender for Legato Software's NetWorker give users the visibility they need to set up the necessary retention policies. CommVault Systems, IBM Tivoli and Veritas Software Corp. also offer similar options for their backup products.
Because some tape cartridges are capable of storing more than a terabyte of information, administrators shouldn't store multiple sets of data with different retention periods on the same cartridge. WORM tape cartridges can't be reformatted, so storage administrators and their organizations could find themselves in a predicament with tapes that have different data retention periods. The best policy is to move data with longer retention periods to another set of WORM tapes.
WORM tape cartridges provide an economical and practical way to comply with the latest government retention regulations. While users of 3592, DLT and LTO tape media will need to wait just a bit longer for this functionality, 9840 and AIT users can begin to implement this technology now. Remember: Failing to set up policies and procedures to manage long-term data on WORM tape could have consequences as dire as if you had not implemented WORM tape at all.
This was first published in July 2004