>>What I've not attempted to do is dd a disk image back to a SCSI HD. It's on
>>my list of things to try, but who knows what decade I'll finally find the
>>time.
>
> I haven't done this on a PDP-11, but have done it with SCO Unix,
>Linux, and FreeBSD drives. It's all geometry. I do know that BSD
>v2 sets partitions on cylinder boundaries, so the principles should
>be the same as in later platforms.
>
> You need a target disk with the same head/sector geometry as the
>source. The number of cylinders is a lot less critical, as long as
>the target isn't smaller than the source.
>
> You can actually get away with using an unmatched target as long
>as fsck never runs. :)
>
> I dunno about other OS disks. The little I know about RT-11's
>filesystem implies that most any old disk should work.
My idea is actually to first dd the HD to a disk image, then prep
that disk image under SIMH or E11. Copy the data I want on the HD to
the image using the emulator, and then dd it back to the HD.
Logically it should work just fine. With RT-11, you shouldn't even
need to dd the HD to a disk image, just create whatever size disk
image and dd it out there. The other OS's would be a bit more picky.
It should be a good way to get a large amount of data onto a PDP-11,
however, I've yet to actually have a need to attempt it (I've just
used Ethernet or CD-R to get data on).
Zane
--
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh_at_aracnet.com (primary) | OpenVMS Enthusiast |
| | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
Received on Wed Sep 01 2004 - 00:51:26 BST