Need DAT Tape Experts! (July 23, 2008)

[KrisV]

Team Technosaur is having trouble getting data off old DDS-1 and DDS-2 tapes. They've been successful in reading Exabyte tapes, but using the same method with the DAT tapes restores an empty (0 kB) file. LOAF adds that Windows Backup detects *something*, but it won't list any actual files. They have HP SureStore DAT24 and Seagate Scorpion tape drives that should be able to read these DDS-1 and DDS-2 tapes. There isn't much time left, so hurry and drop LOAF an e-mail if you think you can help!

Everyone is very busy at Mythic working 12-hour days, but here's a brief status update:

We began the day by finishing up with 3.5" disks (beta versions of various ~1994 games). Charlotte focused on CD ripping and finished almost the whole job. Chris finished major photography today. Scanning began and we found some really interesting WC stuff that we can't reveal yet.

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Original update published on July 23, 2008

 

[Iceblade]

Just a thought, but have you tried cleaning the tape drives. I just read online where these drives are picky about being cleaned regularly and with the heavy use they are getting reading and copying these old tapes, they may be having some difficulties.

Also, these DDS-1 and DDS-2 tapes are 90-meter right and not 60-meter...if they are 60-meter than they make only be read-only compatible on your tape drives but that should mean that they are still able to copy them.

A link for possible solutions: http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=461387

 

[Mace]

There is no detail,

- Are there actually any errors coming from the recovery process?
- Is the drive actually recovering a file by reading from it, and does it just come up after a succesfull restore with 0 kb files that have gibberish for filenames... or does it just blink once and gives you some file?
- You mention windows backup, aka NTbackup, was this the program used to back up?
- and did they use compression features during the backup process through software or hardware?

you can use, with the limited time you have, use DATMAN to copy the raw data on to a DVD, at least you have it then to take with you, and can recover at a later time.

 

[cff]

They might be encrypted and or compressed. While Windows Backup works with tape drives it is aweful at doing so.
My tape drives came with a software to install that looked exactly like the Windows Backup one except for a small add, but had more options.
Windows Backup could NOT read tapes that were written with the other one if compression was selected.

 

[AD]

I need to go to bed but I did come up with this in my google hunt:

"Some DAT devices must be enabled for variable length blocks before they can be read else they produce no data status. This can also happen when the requested block size is lower than the actual block size on tape."

 

[Taser8]

This may be completely irrelevant, but could it be because some of our backups were done from the SGI's using Irix, rather than windows? They might be Irix (SGI's proprietary Unix format) configured - so they'd show something, but Windows Backup wouldn't know what it was....just a thought.

 

[Mace]

That's exactly the reason why i would encourage them to grab an image of the raw data, like in an iso-type format....

They can get to it now, grab all 0's and 1's, and analyze them later. the data could vary from the administration's scanned taxi bills of transporting tom wilson, through the original renderings from wc1(wich i believed were lost?), you never know.

Compression complicates it, but when you open the files with a hex editor usually the compression type used, and it's revision are listed in the header of the file...

They have access to the data rightnow, and possibly never again?

-guys, if you have the chance, please use a DDS4 or DDS5 drive for restoring, the heads are more precise and are better at reading aged tapes-

 

[AD]

That's exactly the reason why i would encourage them to grab an image of the raw data, like in an iso-type format....

They can get to it now, grab all 0's and 1's, and analyze them later. the data could vary from the administration's scanned taxi bills of transporting tom wilson, through the original renderings from wc1(wich i believed were lost?), you never know.

Compression complicates it, but when you open the files with a hex editor usually the compression type used, and it's revision are listed in the header of the file...

They have access to the data rightnow, and possibly never again?

-guys, if you have the chance, please use a DDS4 or DDS5 drive for restoring, the heads are more precise and are better at reading aged tapes-

You are missing the point. That's exactly what they're trying to do, only it's returning a 0KB file.