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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:

    Code:
    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.

    #2
    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.

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      #3
      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).
      Torfinn

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        #4
        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.

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          #5
          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.

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