31 Aug
2004
31 Aug
'04
5:51 p.m.
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.