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imaging a whole hard disk into a file

Al Kossow

Documentation Wizard
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There has to be a simple way to do this in DOS
I have a M-disk disk-on-chip which is a flash disk that presents itself through a BIOS interface.
I'd like to clone it into a DOS file, so I don't have to go through the hassle of finding a DoC
driver for Linux.
 
I've used Norton Utilities 4.5 for sector-imaging hard drives under DOS. It does have some limitations. It can't really deal with bad sectors, which are normal on "MFM"/"RLL" hard drives. It won't split an image for backup to floppies, so the source/destination must be one large drive. Because it is DOS, the maximum file size is about 2GB. It is also all menu driven, not automateable CLI.

The nice thing about Norton is it can access the drive either sectors through BIOS (no partition needed), or as DOS clusters.
 
Hm. I never noticed that feature in the Norton Utilities before. Worth learning. Thanks.
 
I've done something like this to image an MFM drive. The contents were sent over the network to a file, which could then be mounted under VirtualBox or VMWare.

Something like Partition Magic or Ghost should be able to image a BIOS drive to a file. The code is fairly simple - given the geometry of the device, read a sector at a time and write it somewhere else. For spinning rust you want to do a track at a time for performance reasons, but for a solid state device a sector at a time is not a concern.
 
I always use a rather simple (but still GUI-driven) tool called "Partition Image" to do that in DOS. But there are plenty of options, as that's really not a hard task to do.
 
I think Norton Ghost could do this, it runs on top of DOS IIRC.

You have to be carefull with Ghost. The default is to create a "logical" image. when Ghost re-constructs the disk from this its not a sector copy. I expect Al wants a "forensic" image which some versions of Ghost will produce but you need to request it. I used to have a Ghost boot disk that would load a TCPIP stack and ghost to a network share. Very usefull if you DOS machine had a LAN card.

However I thought DOM modules looked like IDE drives so won't it just work in Linux.
 
However I thought DOM modules looked like IDE drives so won't it just work in Linux.
He has a Disk-on-Chip, which is not a DOM. Completely different stuff hardware-wise. Linux needs a driver for that, as Linux does not use the BIOS to talk to the hardware.
 
He has a Disk-on-Chip, which is not a DOM. Completely different stuff hardware-wise. Linux needs a driver for that, as Linux does not use the BIOS to talk to the hardware.

I'm trying to archive a small (32mb) Disk on Chip device from a thin client. I had hoped there was something simple that created a forensic file image of the entire device (not just a single partition) just using the internal
BIOS driver on the chip under DOS, but apparently that doesn't exist.
 
I'm trying to archive a small (32mb) Disk on Chip device from a thin client. I had hoped there was something simple that created a forensic file image of the entire device (not just a single partition) just using the internal
BIOS driver on the chip under DOS, but apparently that doesn't exist.

Thin client? Ok, so I'm guessing the tricky part then is interfacing with a larger drive, and dropping in a network card, second hard drive, or XT-IDE is not possible?

Can it actually boot from a MS-DOS disk and still access the DoC drive? Does it have a serial or parallel port?

If so, one approach I might try is making a boot disk with something like Lantastic Z, which creates a network-style logical mapped drive over serial or parallel port. Then dump the drive contents to file with Norton Utilities or a similar BIOS level took.

Another possibility might be using a parallel port Zip drive. In this case, that would be large enough.

With a device like a DoC, you should not have to worry about bad sectors interrupting the transfer process. Hmm, hopefully they did not copy protect the contents somehow. That would be.... interesting.
 
I would have thought this was something easy that would have been solved literally decades ago; dumping a physical disk through the BIOS interface via DOS onto a local file.

The device has an ATA connector you can boot from, it is trivial to boot DOS on them with a 1Gb CF card.
The file system in the DoC is Linux, so there will be nothing recognizable to DOS

Digging around today I've actually found DoC dumps from another vendor of a similar product, a Nlynx LM-6488 twinax thin client instead of the Visara NCT coax thin client I'm trying to dump.
in the 00's, these vendors actually had downloadable updates.. on ftp sites now long gone.

FWIW, I'd be interested in finding a Nlynx LM-6488 if anyone has one they don't need. Digging on the web, there are lots of people taking these mainframe thin clients, ripping out the firmware
and PCI interface and turning them into routers or DOS boxes. These particular units are interesting in that they are running Linux and not CE or QNX like most of the others do.

LM6488.jpg
 
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You said you don't want to use Linux, but old MINIX variants can run on many generations of x86 and talk to disks through the BIOS. Maybe you could boot up an old MINIX somehow and dd the data you need?

(Thanks to BIOS HD compatibility, it's also the case that MINIX-VMD is a good choice if you want to get a Unix-like OS running on your PowerMac 6100 DOS Compatibility Card #lifehacks)
 
You said you don't want to use Linux, but old MINIX variants can run on many generations of x86 and talk to disks through the BIOS. Maybe you could boot up an old MINIX somehow and dd the data you need?

I don't know what you mean by "old" but none of the minix versions I've been elbow deep into (up to 1.5) go anywhere near the bios for hard disk access.
 
I have some Neoware thin clients that use ATA interface flash, if that's any help. They use the Hyperstone F2-L16XT controller to manage the (Samsung) flash chip. I have them for Linux, WinCE and WinXPE. The interface is bog-standard laptop 2mm 44 pin ATA laptop drive. I have a couple more that use the SST NANDrive.
 
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