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Does this backup format ring any bells?

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    Does this backup format ring any bells?

    I'm looking at a bunch of tapes here that date from around 1990-93, so pre-Win95. They're DOS images, but they're not quite familiar to my eye.

    The interesting thing is that they start out with 64 x 512-byte blocks, all identical that look like this:

    00000000 48 45 41 44 45 52 20 46 52 41 4d 45 00 02 01 00 |HEADER FRAME....|
    00000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
    00000020 01 43 4d 53 00 34 98 39 32 30 32 31 33 39 35 31 |.CMS.4.920213951|
    00000030 36 32 38 00 e0 00 00 00 00 00 00 00 00 00 00 00 |628.............|
    00000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
    00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 c9 |................|
    00000080 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
    00000200 48 45 41 44 45 52 20 46 52 41 4d 45 00 02 01 00 |HEADER FRAME....|
    ...then a tapemark, then the backup data.

    The "CMS" would seem to point at a version of Colorado Backup for DOS, but I don't find any version that will accept this format. Does this look familiar to anyone? Any ideas? I really don't want to write my own restore code for this if I don't have to.

    Fortunately, I didn't have to write my own restore utility. After a lot of searching, I found a file from 1994 in SIMTEL20 called "DAT405.ZIP" with "from CMS" in the one-line description. Thinking that DAT drives back in 1994 were exclusively SCSI, I tried it on my Tandberg 4200 SLR5 QIC drive. It worked. Oddly, it's very fussy about DAT drives--it aborts with an 08 error on a Sony SDT-5000 and refuses to recognize a WangDAT 3400. It doesn't seem to understand 8mm (Exabyte) drives at all and I didn't bother with DLT--I figured that was going to be a lost cause for certain.

    Anyway, FIWIW. Seems that Colorado had several different backup/restore utilities. Some, for example, were limited to handling floppy-interface drives. This particular one is SCSI only--and includes ASPI drivers for only the Adaptec ISA, VLB and IBM MC varieties of those. Fortunately, ASPI is ASPI, so "none of the above" works fine for adapter selection.


      My (fuzzy) memory from those days are that backup programs would require / support only a specific set of tape drives, even if they all were similar (SCSI, DAT, etc).


        This product was from 1992-4; there is/was a standard set of basic SCSI commands for a given device class. That is, a subset that all devices must support. Heaven knows, when I was writing tape backup code back then, I had no problems sticking with a basic set--and it worked over QIC, 8 mm, DAT, DLT, SLT, no problems. My suspicion is that the CMS code was designed for shipping with Adaptec controllers and a specific set of devices. Why it would allow for selection of other devices, but not offer generic support, is a mystery.


          Everex backup is annoying that way as well. I haven't tested it yet since I finally found one of their ISA SCSI cards to test with to see if I can get it to work with SCSI rather than QIC tape drives.