Backing up ST506 disks

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Mon Aug 4 16:42:00 2003

> Hi all,
>
> I'm just wondering how to back up the hard drive (a 20MB MFM) in my Research
> Machines fileserver. The system runs CP/M, has a couple of floppy drives, and
> the hard disk is hooked up to a Xebec controller with a SASI bus linking it to
> the host controller in the fileserver.
>
> There are actually two problems:
>
> 1) Getting the data off the hard drive somehow (possibly via floppy) and
> being able to read it on another system (ideally a PC I suppose)
>
> 2) Being able to rebuild the system if/when the hard drive fails.
>
> Thoughts on both are welcome! I don't have any kind of OS source media for the
> system, and it wouldn't surprise me if it isn't the only survivor :-( Maybe
> there are utilities on the system itself to recreate bootable OS media, but my
> knowledge of CP/M is a little lacking!
>
> For my old SCSI systems I tend to hold a raw block-by-block backup image of the

SCSI is closely related to SASI, and IIRC, a SCSI controller will
normally talk to a SASI peripheral (it often helps if the SASI peripheral
is the _only_ device connected to the controller).

I would keep the drive with the SASI controller (Xebec card). The ST506
interface is a low-level interface, and the data lines are essentially
the raw data to/from the head. So the controller can do what it likes
with that as regards sector marks, data encoding, etc (well, there are
restrictions, but...) So a drive formated and used with one ST506
controller may well not be able to be read by a different ST506 controller.

If you use the Xebec card you should at least be able to pull the raw
blocks off the drive. How you then interpret the resulting filesystem
image is another matter...

-tony
Received on Mon Aug 04 2003 - 16:42:00 BST