Hi,
13.11.2008 21:58, Dan Langille wrote:
> On Nov 13, 2008, at 11:56 AM, Heitor Medrado de Faria wrote:
>
>> Heitor Faria
>>
>> Dan Langille wrote:
>>> On Nov 13, 2008, at 11:16 AM, Heitor Medrado de Faria wrote:
>>>
>>>> Guys,
>>>>
>>>> This is urgent.
>>>> Is there anyway to restore data on tape after an eof?
>>> I have no idea.
>>>
>>> I would guess that it would require something special to force the
>>> tape drive to read past the EOF.
>>>
>>> This is not something Bacula can do AFAIK.
>>>
>
>> Is there anyway of bscan ignore the eof?
>
>
> Please do not reply at the top.
>
> I do not know. I am quite sure that you cannot force bscan to ignore
> the EOF.
>
> This is not a Bacula issue. This is a tape and tape driver issue from
> what I know.
Indeed.
With stupid tape technology - i.e., older ones, and only the ones
without chip memory - you can *try* to position to *before* the EOD
mark, then write a very short block of data, reload the tape, and see
if that was sufficient to overwrite the EOD mark. With luck, you end
up doing this:
Broken tape layout:
Data Block EOF Data Block EOF EOF The data you want to get at EOF
^^^|^^^
tape drives/ drivers interpret this as an EOD mark
After writing:
Data Block EOF Data Block EOF Data unreadable data The data you want
Then, ignoring read errors, you might be able to access the data you
want to get at.
Needs lots of luck (which could be less when knowing the exact tape
technology you use, because, for example, the QIC standards specify
how long a file mar is on tape, how long an EOD mark is, and how long
a block of given length is), the right hardware, and afterwards you
might have to further process you read data.
If you use recent tape technology, I believe there is no way to
achieve what you want. Those tape drives always know where the tape
contents ends, and will not be able to overwrite the EOD mark without
appending a new one.
A commercial data recovery service might be more helpful.
Arno
--
Arno Lehmann
IT-Service Lehmann
Sandstr. 6, 49080 Osnabrück
www.its-lehmann.de
-------------------------------------------------------------------------
This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
http://moblin-contest.org/redirect.php?banner_id=100&url=/
_______________________________________________
Bacula-users mailing list
Bacula-users AT lists.sourceforge DOT net
https://lists.sourceforge.net/lists/listinfo/bacula-users
|
