Tuesday, May 31, 2011

Where, how and why are tapes still used for backup?

Not strictly a TSM only topic, but this fascinating thread has been raging on over at LinkedIn for the last few days and I thought it would be worth sharing here. The provocative question asked was:
"Is tape still used for backup? Why is tape still being used these days when disk and cloud are available?"

Cue an avalanche of fascinating pro- and anti-tape pitches and opinions. Wading through the comments may take a while (I pitched-in with a couple of comments too) but it's a useful read as, frankly, these are the questions that clients/customers/decision-makers - and indeed ourselves - should be asking to ensure that we continue to use the right technology for the right purpose.

Of course, TSM itself is well-positioned for in many ways given its long-running support of disk, both in random access and more recently in sequential file (virtual tapes!).

David Mc
London, UK


  1. I think today tape serves more of an archiving purpose and disk with deduplication/replication is what most businesses should move to. The problem is cost and everywhere I have worked the cost has been scoffed at by management. The initial buy in keeps them from fully implementing a complete solution, and so tape marches on...I remember people saying tape was dead years ago, but it's still here.

  2. Tapes have their place in the backup world and this is not going to change in the near future (if ever).
    Disk arrays, VTLs - all great things. Even better with deduplication - but you have to power them, cool them and I have seen (several times) disk arrays being wiped out clean of data after power surge, multiple disk failure when powering off/on the array after several years of service ... etc.
    It is a good thing to have your data in multiple copies using different technology for each.
    Another reason(s):
    1) Although it is very convenient to replicate data between sites, even with deduplication you may need huge bandwidth to transfer the data in the given time. Moving one or one hundred tapes - not a big difference.
    2) Tapes taken offsite are safe solution. They are offline, not accessible directly - so no one can accidentally or intentionally delete them. You cannot say this about (almost) any online solution.

  3. Harry,

    I agree, the problem I have seen is that tape solutions usually can't meet SLA restore times (usually because the customer doesn't collocate the data.) It all comes down to solutioning to meet business requirements. Now if companies only had good SLA's.