[Info-vax] Backup TK50 tapes

[Johnny Billquist]

On 2013-02-24 19:08, Bill Gunshannon wrote:
> In article <kgdc06$jik$1 at iltempo.update.uu.se>,
> 	Johnny Billquist <bqt at softjar.se> writes:
>> On 2013-02-23 14:48, ChrisQ wrote:
>>> On 02/23/13 13:09, supervinx wrote:
>>>>> Are you using standalone backup here, or the BACKUP available from the
>>>>> VMS prompt?  ISTR that standalone backup supplied with VAX-VMS doesn't
>>>>> offer the full functionality of the command line version.
>>>>>
>>>> No, I'm using the CLI backup...
>>>>
>>>>> I think if you use the virtual tape emulation of LDDRIVER to mount an LM
>>>>> device you should be able to copy from physical tape to virtual tape.
>>>>
>>>> It seems that BACKUP can't go /PHYSICAL on input tapes, since it treats
>>>> them as savesets...
>>>>
>>>
>>> If you can find a TK50-Z scsi tape drive, you may be able to use Linux /
>>> unix
>>> and dd to copy to files. There may also be later scsi versions of TK50
>>> drives
>>> as well.
>>>
>>> The TK50-Z is a bit old now, but was the optional tape drive for the VS2000
>>> series machines...
>>
>> That will totally not create anything useful for him.
>> Unix, in all it's "glory" really sucks at some things. Record-oriented
>> devices is one of those things.
>> If you use dd, you'll have a lot of digging to do later, in order to get
>> something useful out of the results.
>
> Guess it depends on what youi consider a lot of digging.  I used dd to
> rebuild the Ultrix-11 boot tape with all the correct blocking to make
> it work again.

Ultrix-11 tape are "nice" in that there are actually just a few 
different record sizes, and once you know them, and some additional 
meta-data, it becomes at least reasonably possible to recreate the 
blocking. For other tapes, it can be much more "interesting".

And for the record, as far as I am aware, all Unix bootable tape 
distributions I know of have a similar easy pattern for record sizes. 
But even so, naively using dd will not give you something useful.

	Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
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