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prageethh's avatar
prageethh
Level 3
2 years ago

What is the recommended number of mounting count for IBM LTO 7 tape.

Hi All, What is the recommended, number of mounting count for IBM LTO 7 tape? BR, PrageethH  
Linux
LTO7
Mount
  • Nicolai's avatar
    Nicolai
    2 years ago

    Mounting count really doesn't matter. What most important is the number of passing over the read/write head.

    Default durability for LTO is 1 million pases. That doesn't mean the tape will last 1 million writes because the tape pases the R/W head multiple times during a full tape write. LTO has 3584 tracks and each band is 32 track. Meaning a full tape write is 112 pases.

    So lets count a bit :

    Shortest retention = 1 month
    Life span (estimate) 4 years

    Then tape will be written 12*4 = 48 times * 112 passes = 5376 for a life span.

    Then we have to count for shoe shining, start / stop operation etc - let's add 50% then the number of passes = 8064 passes. Plenty off room to the 1 million pases. Best case scenario off case.

    Found this PFD who cover the topics well : 

    https://iscgroupllc.com/wp-content/uploads/2012/05/ISC-White-Paper-Lifespan-of-LTO-Tapes.pdf

Nicolai's avatar
Nicolai
Moderator

Mounting count really doesn't matter. What most important is the number of passing over the read/write head.

Default durability for LTO is 1 million pases. That doesn't mean the tape will last 1 million writes because the tape pases the R/W head multiple times during a full tape write. LTO has 3584 tracks and each band is 32 track. Meaning a full tape write is 112 pases.

So lets count a bit :

Shortest retention = 1 month
Life span (estimate) 4 years

Then tape will be written 12*4 = 48 times * 112 passes = 5376 for a life span.

Then we have to count for shoe shining, start / stop operation etc - let's add 50% then the number of passes = 8064 passes. Plenty off room to the 1 million pases. Best case scenario off case.

Found this PFD who cover the topics well : 

https://iscgroupllc.com/wp-content/uploads/2012/05/ISC-White-Paper-Lifespan-of-LTO-Tapes.pdf