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On our production setup we are using LTO 5 for taking backup on weekly basis, Unfortunately we do not have any purchased document for LTO5 tapes due to which we are unable to predict the exact EOL(End of Life). We have linux servers connected to MSL Tape library , What is the way by which I can find out the exact expiration date of LTO5 tapes?

Mahesh Morankar
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There is no expiration DATE as much as a recommended max number of "runs", which your software should count. And guess what - that depends on the TAPE. Look up the documentation for your tapes from - guess what - the manufacturer.

The official text says, for example: "Ultrium media is certified for 1 million passes or 260 full back ups and has a 30-year archival storage life."

TomTom
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    From [wikipedia](https://en.wikipedia.org/wiki/Linear_Tape-Open#Tape_durability): *LTO tape is designed for 15 to 30 years of archival storage. Depending on the generation of LTO technology, a single LTO tape should be able to sustain approximately 200-364 full file passes*. +1 from me! – MadHatter Apr 22 '16 at 07:12
  • okay and "regularly writing only 50% capacity of the tape results in half as many end-to-end tape passes for each scheduled backup, and thereby doubles the tape lifespan" it means I can use those tape upto 30 years at least if I am using half of portion for writting. – Mahesh Morankar Apr 22 '16 at 07:25
  • Not sure why you talk about yearhs. ARCHIVAL STORAGE is not use. It is storage under defined archival conditions. But generally - yes. I would cycle tapes regularly, but that REALLY may mean "when replacing the drives" ;) – TomTom Apr 22 '16 at 07:30
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What I do is dump out the drive's log pages at the end of each read and write. Since we are producing tapes for long term archive this gives us the confidence that what we have written is good. If you go to the LTO drive manufacturers website you can download the SCSI reference manual. (From LTO7 , all drives manufactured by IBM) Under LOG SENSE you will find a definition of the log code pages which give a huge amount of information about the tape and the drive. We routinely monitor corrected and uncorrected error count which is a good indicator of degrading tape/drive and this is non-destructive. The HP and IBM diagnostics will do a reasonable job on testing drives/media. It's not just a question of the tapes , but more about the drives. The more worn the drive head is the more data correction you will get.

J R Spigot
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    For anyone reading this answer and wondering how to do as described: this can be done with `sg_logs -a /dev/nst0` from the `sg3-utils` package – Dark Mar 08 '20 at 19:46