[Simh] VAX Tape Emulation?

[Johnny Billquist]

Zane - unless I remember wrong, there is a tool from DECUS to copy tapes 
to a file image, and then get that back to a tape again. The RSX version 
is called TPC, and I'm pretty sure it also exists for VMS.

Using that, pull your physical tapes into files, copy the files over to 
the simulated machines, and write them back out to simulated tapes there.

   Johnny

On 2018-01-25 16:17, Zane Healy wrote:
> Just to be clear, I’m looking to backup a physical machine, to a virtual 
> tape drive, such that I can restore the data to either SIMH or a 
> Physical machine.  I don’t need to extract files.  I can extract files 
> (and I have with some of the most critical) via NFS to my Mac.
> 
> Except for legacy hardware, most tapes I dealt with in the 90’s were in 
> the 20-40GB range.  Current tapes now are multi-Terabyte, but not 
> something most of us can afford to have at home, which is why I’m 
> looking to go this route.
> 
> Zane
> 
> 
> 
> 
>> On Jan 25, 2018, at 5:39 AM, Tim Shoppa <tshoppa at gmail.com 
>> <mailto:tshoppa at gmail.com>> wrote:
>>
>> A couple of the tape image utilities I wrote or updated in the 1990s 
>> have that limit. Let me see if they are still in the SIMH utility 
>> tree. They never would’ve bitten me back in the 90s because the 
>> biggest reels I ever dealt with were 3600 feet at 6250 BPI, less than 
>> 250 Mbytes.
>>
>> Tim
>>
>> On Jan 25, 2018, at 8:23 AM, Johnny Billquist <bqt at softjar.se 
>> <mailto:bqt at softjar.se>> wrote:
>>
>>> Hmm. None of the tools I wrote ever had that limit. They just process 
>>> records and don't give a damn about absolute disk or tape position.
>>>
>>> Johnny
>>>
>>>
>>> Tim Shoppa <tshoppa at gmail.com <mailto:tshoppa at gmail.com>> skrev: (25 
>>> januari 2018 00:53:34 CET)
>>>
>>>     Many common tape image tools as of two decades use 32-bit
>>>     integers to carry offsets around and will be limited to 4Gigabyte
>>>     tape image sizes.
>>>
>>>     I don't think this is a fundamental limit to the tape image
>>>     formats used by SIMH, just a common limitation of the tape image
>>>     tools you might find from 20 years ago.
>>>
>>>     Tim.
>>>
>>>     On Wed, Jan 24, 2018 at 5:02 PM, Zane Healy <healyzh at avanthar.com
>>>     <mailto:healyzh at avanthar.com>> wrote:
>>>
>>>         What type/size of tapes does the VAX emulation support?  I
>>>         was looking through the doc’s and it wasn’t obvious to me. 
>>>         Is there a size limit?
>>>
>>>         Thanks,
>>>         Zane
>>>
>>>
>>>
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-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol