Troubleshooting Copying LTFS Tapes Back To Drive w/ Cache-A

[Tom Goldberg]

Dean,

You did not provide quite enough info here – in your Tape Information, what was the “Space Lost” value? If that is small, the files should be there, if that is close to the 1059GB used, then something is likely very wrong with the tape.

The fact that you see the files when displaying “LTFS Volume” tends to sound like they are there – two things to try:
1) first eject the tape, delete it from the catalog and then reinsert it to have the Cache-A relearn it; that may clear up the problem
2) if that doesn’t work, try the Recover All function under the menu button

If neither of those work, you might want to check how the tape performs on any other LTFS device – it should be fully readible under PreRollPost or YoYotta or even the free LTFS distro.

I hope that helps.

Tom Goldberg
TGCS
30201 Rainbow Hill Rd.
Evergreen, CO 80439
mailto:tomgoldberg@gmail.com
https://tomgoldberg.net

[Dean Karoliszyn]

Hi Tom–

Thanks for responding to my message!

Unfortunately, it looks like the “Space Lost” value on these affected tapes matches the total space used on the tapes.

Also, I tried deleting the catalog for re-inserting the tape, but it gave me the same result as before. Lastly, the “Recover All” button is greyed out in all scenarios I tried setting up.

Any more information that I can provide/will I need to use some sort of data recovery on these tapes?

Thanks,

Dean

[Tom Goldberg]

Dean, that is bad news indeed. It means that the Cache-A really doesn’t think any files got successfully written to to tape (it sounds like the directory got written to its partition but that doesn’t mean the files were actually written to the data partition). Also, you should have seen solid errors filling the archive sessions that wrote those files. 100% data loss and zero files means that the Cache-A will not be able to recover anything. The only thing I could suggest you might give it a try on other LTFS software – I think PreRollPost has a rebuild function that could actually scan the data partition for what’s really there.

Tom Goldberg
TGCS
30201 Rainbow Hill Rd.
Evergreen, CO 80439
mailto:tomgoldberg@gmail.com
https://tomgoldberg.net

[Dean Karoliszyn]

That’s odd, considering I haven’t gotten any error messages while writing any of these tapes, they were all “successful,” no hiccups…could it be a case of outdated software? I haven’t updated in over a year…

In order to use PreRollPost, will I need a new machine? Aka, I’m guessing PreRollPost is not compatible software to use with a Cache-A appliance? I did a brief search of the PreRollPost site, and it claims compatibility with HP, IBM, Quantum, mLogic and Tandeberg models.

Thanks for the help,

Dean

[Tom Goldberg]

The problem isn’t old software as Cache-A sold its assets to ProMax in September of 2014 and they have not released any new software for the original hardware since that time. The LTO-6 models are all running the final release v3.4.3.

I’m surprised you didn’t see any errors – did you ever check the Tape Info in the past? Did it ever indicate that files were really there? I’ve never seen that dialog report change over time, and we always recommended verifying that report before putting a tape away for archive.

Yes, PRP won’t run on the Cache-A and will require a Mac and a SAS card with any LTO drive or a Mac and a Thunderbolt LTO drive like the mLogic. I’m just thinking maybe you could find a third party that has some alternative way to read LTFS tapes to see if something is going on with your Cache-A. You might alternatively try a new archive on the Cache-A with a different tape to see if you can successfully write and recover newly written files.

Sorry that I can’t be more helpful in this case.

Tom Goldberg
TGCS
30201 Rainbow Hill Rd.
Evergreen, CO 80439
mailto:tomgoldberg@gmail.com
https://tomgoldberg.net