Recovering data from 4mm and 8mm tapes

[Chuck Guzis]

On 03/23/2015 08:46 AM, Douglas Taylor wrote:

> I have a couple of 4mm and 8mm tapes that contain data I want to
> recover.  The 4mm is DDS-1 and was written using tar on a SGI system in
> 1998.  My questions are;
>
>   'What modern DAT tape drive will read this tape?  How backward
> compatible is this technology?'

Depends largely on the manufacturer.  For example, a QuantumA DDS-4 
drive should be backward-compatible.  For other brands, check the 
manufacturer's specification.

> This seems like an easy problem and intend to use a linux system to read
> the tape.

Frankly, it's probably better to use the same software to restore the 
tapes that wrote them than trying to suss out the results of a plain dump.

  The 8mm tapes were also written on an SGI system, however it was in 1994
> and the IRIX Backup utility was used.  IRIX 5 was probably used.  Any
> ideas?

Exabyte 8mm tapes, like DDS tapes, were pretty good in conforming to 
SCSI tape standards, so they should work just tine, provided that you 
have the right drive.  For 1994, an 8700 should do the job.

Of course, you'll have to deal with the block size issue if these are 
not Unix-native, but that's been discussed before here.

--Chuck