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I am trying to understand tape load/unload cycle in a data center setting. As far as I understand, tapes and tape drives, both have load/unload cycles. So each time a tape is loaded into a tape drive which is then loaded into a tape library, does load cycle count increase for both (cartridge and drive) of them?

I checked tape cartridge specifications at this site and tape drive specifications, for Quantum LTO-6, at this site.

Also, as data is read more and more, how does it affect media, drive, and library's reliability? I understand that as tape cartridge's and tape drive's load cycles are done, they need to be replaced but does it affect their failure rates as well?

I need to simulate a tape archival system for an academic project.

Pretty
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What are the consequences for Tape Failure? It is far better to error on the side of safety. I would require tape replacement at less than 20k load cycles and if the tape drive error rate spikes reading or writing to the tape. HP reports the read/write error rates is the best metric. They in extreme testing only went to 25k cycles so that gives you an idea.

Yes very roughly as cycle count increases error rate increases as well. Crudely as cars get to say 200k+ miles they often have increased items needing to be fixed or replaced. Any issues with temperature or humidity in your environment you can really cut into that safety margin.

I recall an anecdotal report that a tech was eating peanut butter and jelly sandwich and contaminated a tape which ended up causing massive contamination of many tapes and drives.

So how does HP ensure its storage media is always reliable? Simply by performing the most comprehensive study of error rates, capacity and transfer rate that technology can deliver. Error rates tell us how much margin there is before failure. Did the backup and restore operation only just complete successfully, or did it complete with lots of margin? Poor error rate can lead to slower transfer rates, reduced cartridge capacity and, ultimately, backup and restore failure.

Variations in climate and humidity play a significant part in the stability and performance of tape media. Every customer is different, however, so unique diagnostic tools like HP TapeAssure can help you identify when it may be time to replace your media and keep your backup and archiving running smoothly. http://www8.hp.com/h20195/V2/getpdf.aspx/4AA4-4580ENW.pdf?ver=1.0

Please don't just verify backup data but do full scale test restores and write procedures. This also helps you how long it will take.

Edit: Another stack question answer discusses maximizing tape life best practices.

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  • Thanks but I am still looking for an answer to my questions. I need to simulate an archival system and understand how read/write would affect tapes, tape drives, and tape libraries over time. – Pretty Sep 03 '15 at 03:19
  • Is this an academic project or something requested by management? Can you edit your question to provide more information on what you are trying to do? Some answers may need real-world testing and recording data. – StackAbstraction Sep 03 '15 at 17:42