Offsite data storage with tape: Storage best practices

What are your offsite tape storage practices? Do you send tapes offsite one by one or in batches? Either way, there may be some drawbacks.

What are your offsite tape storage practices? Do you send tapes offsite one by one or in batches? It's fiddly to label each tape with a unique identifier or barcode used by the offsite data storage provider. For a start, where would you place such an identifier? For most of us, it's less onerous and time consuming to remove your tapes in batches just in time for a man in a van to turn up, zap each case identifier and present you with a printout of the case numbers to be shipped offsite, as well as the cases that will be returning.

Why use offsite backup tape storage in the first place? For the majority of us, it's probably for disaster recovery (DR) purposes. The longer backup tapes remain on site, the greater the chance they'll be damaged. It's difficult to perform a DR operation if you can't read the barcodes on a tape that was charred in a fire, never mind the impossible task of forcing a melted plastic cartridge into a drive. By the way, I don't believe your disaster recovery services provider would be happy at the thought of such tapes being forced into their hardware.

If your tapes contain primary backups, it's fair to assume you'll recall offsite tapes to fulfill restore requests. And it's also fair to assume they'll be delivered in the same way they were shipped -- per case, assuming you hold records linking the media and case details.

So why can't individual tapes be recalled? Because the individual tapes in each case don't have an offsite identifier; therefore offsite tape storage vendors won't (or shouldn't) open cases to retrieve individual tapes. Currently, if there's a breakdown in the records linking the media and case identifiers, all cases are returned to the customer. But this means that all of your offsite media is on site once again, which is precisely what you tried to avoid when you began this process.

There's no way to eliminate this possibility, but there is a compromise: label individual media with an offsite identifier or barcode. I know that's what you wanted to avoid in the first place, but I'm arguing that it's worth your time. However, where do you put this identifier or barcode? And assuming there's a place for it, will your man in the van be happy to scan 400 tapes per visit? You'll have to ask him. And if he does agree, how long will the scanning take? Remember, the longer tapes remain on site, the greater your risk.

About the author: Hywel Matthews is a senior consultant at GlassHouse Technologies (UK), a global provider of IT infrastructure services. Matthews has more than 12 years of experience in the IT Industry and nine years of experience in backup, recovery, disaster recovery, systems and storage.

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