Tape Labeled in error

[Steve999]

Does anyone know if it’s possible to recover data from a tape that has been labelled in error? One of our archive tapes somehow got mixed with the general tapes and had it’s label overwritten.

Legato say it’s not possible with any of their tools and suggest using a data recovery service but cannot guarantee that the data will be readable once recovered. Has any one had any experience of a successful data recovery from a Netwoker tape?

 

[605]

Yes, it works. Due to NetWorker's Open Tape Format,
you can in fact recover each single data block.

However, there is a problem:
Labeling also moves the logical end-of-tape to its
beginning (right after the label). Today drive's
firmware does not allow you to pass this point.

You have the choice:
1. Bring the media to a data recovery company which will
help you. This will recover all data but will also
cost a fortune.

2. You can get rid of the logical EOT by writing a new
save set and then interrupt the process so that NW
is unable to write the double filemark (EOT mark).
I tested this a while ago - i just switched off power
on my standalone device.

It will take a while for NW to synchronize and it can
do it ONLY when encountering the NEXT save set. So you
will in fact loose data. However, if you do not need
the beginning save sets, this is a possibility.

-----------------------------------

Now, before you ever do this on a valid tape, test it.
Please keep in mind that this method is of course not
supported by Legato.

 

[Steve999]

Thanks for your responce.

I've tried this on a test tape and do not seem to be able to get the data off with the scanner command.

It reads the first save set that has over written eot but does not want to continue past this point. Any help would be much appreciated.

 

[605]

This has been extensively described the following doc:

ftp://ftp.legato.com/pub/NetWorker/German/tdocs/tids_2002.pdf

Yes, it is an english document.
Start reding in section 23, page 15.