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Backup Exec Shows LTO3 Media Type Available for Ultrium 2 Drive??

My Backup Exec 11d is showing the my old LTO2 (Certance Ultrium 2) tape drive can read and write LTO3 tapes.


Has anyone heard of this?  Is this possible?
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David
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Well, technically one can programmatically initialize a LTO3 tape with the initialize tape command, and set the density bits to the lower LTO2 setting.

But this is not a free lunch, you'll end up with a LTO3 tape that is effectively reformatted to be a LTO2 tape.  (And this might not work on all LTO mechanisms or even tape vendors.  One of those quirky things one can do in the lab, but I would not recommend doing so with data you care about.)
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Dennis_Atkins

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Interesting.  Any idea why Backup Exec reports it as being able to read and write to LTO3?
probably a bug.
An LTO2 drive shouldn't be able to read or write an LTO3 tape, the compatability is for new drives being able to read and write previous generation formats vis:-

The LTO Ultrium compatibility is defined with two concepts demonstrating investment protection: 1) An Ultrium drive can read data from a cartridge in its own generation and two prior generations. 2) An Ultrium drive can write data to a cartridge in its own generation and to a cartridge from the immediate prior generation in the prior generation format.
(from www.lto.org/About/faq.html)

Any chance of a screenshot to see what you mean about BE saying  it can read and write  newer tapes?
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No, one can absolutely program a LTO family tape and/or media to have a different density and even available block count per the ANSI spec, as well as vendor/product specific settings.  I've written code to do that.

Now the firmware for any particular make/model of LTO family device MAY make some of the bits read-only.  The ANSI spec does not require read/write capability in these settings.

But I assure you, it can be done on some models. I dont have the vendor/product specific programming model for this particular drive.  But if one looks at the document below for a different LTO drive, you can see that several commands exist that can be used to change capacity.  The SET CAPACITY command is required per ANSI spec, which dictates how much is usable.  

The REPORT DENSITY SUPPORT & READ BLOCK LIMITS will tell you the art of the possible for that particular LTO.   MODE SENSE/MODE SELECT will let you control defaults on how the tape itself behaves.

Anyway, I do this sort of stuff professionally all the time.   I can say with 100% confidence level it is POSSIBLE  (There are other commands one can use, but if anybody cares enough to just see what is possible with this particular LTO, look at the link)

Page 92 is pretty good.


http://docs.oracle.com/cd/E21418_01/en/CRCM2172/CRCM2172.pdf
I don't think you're right, a SCSI command is not going to change the number of tracks on the tape head  or change the write current to some value it was never designed to operate at for example. If you can do that programatically then why on earth do HP et al spend so much money designing tape drives? They could just give you a pile of LTO4s and get you to upgrade them to LTO8s programatically.

Question is not about what a drive can and can't do anyway, it's about what that tab means in Backup Exec.
Also was just wondering why it showed up?  I don't really want to force it to do it.  It was just odd the way it reported the media types.  How it showed the detailed info for some of the tapes and not others.  Have to admit it got my hopes up.  Double the space on LTO3's would be awesome without investing in new hardware.
Unfortunately not even dlethe can do that. He might be able to tell the LTO tape drive to claim it's a DLT an I can certainly mess up the barcode rules so that BE thinks tapes labeled with LTO5 labels run in DLT drives but in reality it's down to mechanical, electrical and magnetic properties rather than software.
But a program can change tape headers and operational settings on some drives, in such a way that it totally confuses backup exec. We have no idea how BE differentiates LTO2 from LTO3.  Is it looking at tape headers, or mode pages, or capacity

I am absolutely aware of some devices that have hidden features, capacities and such where sending a 10 byte SCSI command can make something that sells for $1000 magically turn into something that sells for $2500.  

You can't double the space of a LTO2 to LTO3, but it is *possible* that a LTO3 product is lurking out there that is programmatically downgradable to a LTO2, and the only thing that differentiates the two is a sticker and factory-default programmable settings.

Personally, I doubt this is the case. I think it is just a stupid bug, but you can absolutely change a lot of settings on LTOs as this particular manual proves that could cause BE to be confused.
Why on earth would HP do this?    I won't speak for HP, but I know for a fact that this is done every day with hard drives in general.  Economy of scale and all that.  Cheaper to make 1 product instead of 100 and then program the disk to deliver the capacity or features you need.
It's really not that big of a deal.  I was just wondering about why it showed the media types the way it did.
Hard drives are a bit different than tape drives David. The media is inside a hard drive so you can change the capacity programatically to be lower. With tapes the media is separate from the drive so although you may be able to get the drive to lie about its generation it won't then work with tapes it is meant to work with. If you told an LTO5 to claim it was an LTO2 for example it wouldn't be able to read LTO2 tapes (except for the LTO5 tapes that you had painted purple and written "LTO2" on with your felt pen.

(Sorry to go on Dennis, but your question is answered, that tab is populated not from the tape drive's physical properties but from a simple list of barcode label makes that were available when BE was written, that's why the opportunity is there to define other custom labels.)