Can this be done? I've found more than one reference that appears to
imply that if your machine boots from a SCSI disk that you cannot add an
IDE drive. Surely I'm misinterpreting what I've read.

FWIW I'm trying to add an IDE disk to a running SCO 3.2 system that
already has a single SCSI hard disk (2 partitions) and a SCSI tape
drive. I was hoping to "image" the disk to an IDE drive for setting up a
newer system.

The bios sees the new IDE drive, but no combinations of mkdev hd x x
seem to work.

Is this approach doomed from the start? Should I just move the SCSI
controller and drives to the new box?

Any comments appreciated.

Scot Shepherd <b2xuyli02@sneakemail.com> wrote:
>Can this be done? I've found more than one reference that appears to
>imply that if your machine boots from a SCSI disk that you cannot add an
>IDE drive. Surely I'm misinterpreting what I've read.

Actually, that depends on your BIOS nowadays.

>FWIW I'm trying to add an IDE disk to a running SCO 3.2 system that
>already has a single SCSI hard disk (2 partitions) and a SCSI tape
>drive. I was hoping to "image" the disk to an IDE drive for setting up a
>newer system.

>The bios sees the new IDE drive, but no combinations of mkdev hd x x
>seem to work.

>Is this approach doomed from the start? Should I just move the SCSI
>controller and drives to the new box?

I would..

There's much more in the FAQ:
http://aplawrence.com/SCOFAQ/scotec2.html#mixide

--
tony@aplawrence.com Unix/Linux/Mac OS X resources: http://aplawrence.com
Get paid for writing about tech: http://aplawrence.com/publish.html

Scot Shepherd wrote:

> Can this be done? I've found more than one reference that appears to
> imply that if your machine boots from a SCSI disk that you cannot add an
> IDE drive. Surely I'm misinterpreting what I've read.
>
> FWIW I'm trying to add an IDE disk to a running SCO 3.2 system that
> already has a single SCSI hard disk (2 partitions) and a SCSI tape
> drive. I was hoping to "image" the disk to an IDE drive for setting up a
> newer system.
>
> The bios sees the new IDE drive, but no combinations of mkdev hd x x
> seem to work.
>
> Is this approach doomed from the start? Should I just move the SCSI
> controller and drives to the new box?

That would probably be easier.

It _is_ possible to have a SCSI root drive and IDE secondaries under
OpenServer. But it requires a degree of kernel surgery that is not a
good idea unless you are an experienced kernel surgeon.

Another possible easier route: take the SCSI subsystem out of the old
box, set it aside. Do an IDE install there (on the old system). Use
`mkdev hd` and `mkdev tape` to add the SCSI drives back into the system;
physically add the hardware back after the relink (during the subsequent
reboot). (It isn't really necessary to remove the SCSI hardware, but I
recommend doing so because then there is _no_ chance the IDE
installation will harm anything on the SCSI drive. If it's physically
present then there are a few odd scenarios that can unfold; for
instance, if the install kernel fails to recognize the IDE drive for
some reason, you'll end up installing on the SCSI disk and blowing away
contents of the drive you're trying to preserve. If the SCSI disk isn't
present and the IDE drive isn't recognized, the install will just safely
fail.)

>Bela<

Bela Lubkin wrote:
> Scot Shepherd wrote:
>
>
>>Can this be done? I've found more than one reference that appears to
>>imply that if your machine boots from a SCSI disk that you cannot add an
>>IDE drive. Surely I'm misinterpreting what I've read.
>>
>>FWIW I'm trying to add an IDE disk to a running SCO 3.2 system that
>>already has a single SCSI hard disk (2 partitions) and a SCSI tape
>>drive. I was hoping to "image" the disk to an IDE drive for setting up a
>>newer system.
>>
>>The bios sees the new IDE drive, but no combinations of mkdev hd x x
>>seem to work.
>>
>>Is this approach doomed from the start? Should I just move the SCSI
>>controller and drives to the new box?
>
>
> That would probably be easier.
>
> It _is_ possible to have a SCSI root drive and IDE secondaries under
> OpenServer. But it requires a degree of kernel surgery that is not a
> good idea unless you are an experienced kernel surgeon.
>

I've been called much worse things than an "experienced kernel surgeon"

> Another possible easier route: take the SCSI subsystem out of the old
> box, set it aside. Do an IDE install there (on the old system). Use
> `mkdev hd` and `mkdev tape` to add the SCSI drives back into the system;
> physically add the hardware back after the relink (during the subsequent
> reboot). (It isn't really necessary to remove the SCSI hardware, but I
> recommend doing so because then there is _no_ chance the IDE
> installation will harm anything on the SCSI drive. If it's physically
> present then there are a few odd scenarios that can unfold; for
> instance, if the install kernel fails to recognize the IDE drive for
> some reason, you'll end up installing on the SCSI disk and blowing away
> contents of the drive you're trying to preserve. If the SCSI disk isn't
> present and the IDE drive isn't recognized, the install will just safely
> fail.)
>

I understand this approach and I'd thought of this but I don't have the
source to reload the OS fresh on the IDE drive. I'm just trying to help
a friend avoid a rather expensive upgrade offered by the vendor of the
software he is using. Fortunately, I only promised I would attempt to
pull this off.

I'm currently using a complete duplicate backup system that he had from
another now closed store, so his real LIVE data is in no danger no
matter how bad I screw up. If I succeed I just have to duplicate the
effort on the real machine.

Scot

>
>>Bela<

Scott McMillan wrote:
> On Mon, 01 Sep 2003 11:13:52 -0500, Scot Shepherd
> <b2xuyli02@sneakemail.com> wrote:
>
>
>>Can this be done? I've found more than one reference that appears to
>>imply that if your machine boots from a SCSI disk that you cannot add an
>>IDE drive. Surely I'm misinterpreting what I've read.
>
>
> As Tony stated, this depends on the BIOS in your system.
>
>
>>FWIW I'm trying to add an IDE disk to a running SCO 3.2 system that
>>already has a single SCSI hard disk (2 partitions) and a SCSI tape
>>drive. I was hoping to "image" the disk to an IDE drive for setting up a
>>newer system.
>>
>>The bios sees the new IDE drive, but no combinations of mkdev hd x x
>>seem to work.
>>
>>Is this approach doomed from the start? Should I just move the SCSI
>>controller and drives to the new box?
>>
>>Any comments appreciated.
>
>
> If I'm reading this correctly, you want an IDE drive containing your
> current SCO installation to be placed into a new system. I would
> strongly suggest you look into one of the Supertars to help you
> migrate to a different harddisk subsystem - See
> http://aplawrence.com/Reviews/supertar.html
>

Thanks, Tony's FAQ's have been very helpful. I'm to the point where I
should be able to add the IDE drive and start copying data.

However, I did not think about the issues you mention below and I agree
I just may be wasting my time. I'll know for sure a little later this
morning. I'll report back just for informations sake.

Thanks guys for the very valuable advice and assistance.

Scot

>
> Couple of things I see that may present you with problems:
>
> 1) Add-in cards. Failure to get your [NIC, serial I/O, etc.) cards
> to use the same I/O and/or IRQs in the new system may be more hassle
> then you are prepared to deal with. (We have also found that many of
> the newer systems are using _only_ 3.3V PCI slots, and the older PCI
> cards we use are 5V.) I have found it to be much easier in many cases
> to remove the drivers for these cards from the kernel before swapping
> them into the new system, then reinstall the drivers.
>
> 2) OS Compatibility. What version of SCO are you running? (uname
> -X) For example, SCO would not support <5.0.6a on a Pentium 4 system.
>
>
> Scott McMillan
>