On 2021-05-20 4:01 p.m., Warner Losh via cctalk wrote:
On Thu, May 20, 2021 at 1:56 PM Antonio Carlini via
cctalk at classiccmp.org> wrote:
I'm running Linux Mint (an ubuntu derivative)
and I want to mount ULTRIX
CDROM discs to see what I can see.
(I'm eventually going to image these, but I presume that will "just
work" with dd or ddrescue).
They are supposed to be UFS format (according to the net) and that
usually means you have to tell mount exactly which option to use (as not
all UFS implementations are compatible).
I've tried (all the options I can find) and failed:
$ sudo mount -t ufs -o ufstype=44bsd /dev/sr1 /tmp/mount
44bsd is likely too new. ufstype=old or =sunos or =sun might work.
Setting ufstype=sun will indeed work for loopback mounting Ultrix CD images.
With physical CDs, the Linux CD-ROM driver expects the filesystem to use
2048 byte blocks but the UFS CDs have 512 byte blocks. So you'll also
have to add "loop" to the options:
sudo mount -t ufs -o ro,ufstype=sun,loop /dev/sr1 /tmp/mount
That will mount the physical CD using a loopback device so you can
access the 512 byte per block filesystem. (FWIW, I learned that trick
with IRIX EFS CDs, which have the same problem.)