Subject: mounting stackered drives.
From: [email-masked] (Corey Sweeney)

Hello.  I read in a FAQ that it's not possible to mount stackered drives for
linux, So i figured i'd correct this myth right now.

The following is a method of mounting any type of filesystem that you can mount
under dos, for linux.  It's quite slow, and should not be used as a permanant
filesystem, untill someone finds a faster way.  It could be usefull for moving
all your old dos files compressed on a volume over to the linux filesystem
though.

Please don't ask me if you have troubles with this, because i haven't tried it
yet.

From: [email-masked] (Johannes Stille)
Subject: accessing Netware and compressed DOS drives with dosemu+SOSS
Date: Fri, 22 Apr 1994 00:49:46 +0300

Hello everyone, hello James MacLean!

Just as a test, I have done what I proposed:
I run SOSS under dosemu, using a SLIP connection over a pseudo tty.

With this setup, it would be possible to access stackered/doublespaced/
superstored DOS drives as well as Novell Netware servers from Linux. I
have neither, so I can't try it out, but there is no reason for this not
to work.

The SLIP connection over an emulated serial device is very slow. On a
486/33 I got about 1.3 KB/s. If there is sufficient interest, I'd try to
write a special network driver for Linux and a special packet driver
that directly connects to the Linux driver, this would be very much
faster.

So if the method described below is useful for you, please tell me so.
One the one hand, I'd like to hear about success/problems with
compressed drives and with Netware, on the other hand, the more people
mail me, the more I will be inclined to write the faster drivers.

Here is what you need to do:

0. Some of the instructions might be slightly inaccurate, as I use
non-standard networking code. But most probably these instructions are
not affected by the differences.

1. You should have a Linux system with a current kernel and the current
network utilities. You especially should have slattach (dip will
probably work, but is not really made for this kind of connection). If
you don't have slattach, get the net-0.32b package from
sunacm.swan.ac.uk (don't know the exact directory).

You also should have a current release of dosemu. What is really needed
is the serial port emulation. Also, if you want to access a Netware
server, you need the linpkt support.

2. You need the ETHERSLIP driver from the Crynwr packet driver
collection. I found it in a file "pktd11b.zip" on some ftp server.

And of course you need the SOSS NFS server. I found it in a file
"soss32.zip" on some ftp server.

3. Set up dosemu. If you want to access compressed DOS disks or Netware
servers, include the appropriate drivers in your CONFIG.SYS and
AUTOEXEC.BAT. (I don't know the details.)

4. Now edit the dosemu configuration file to contain something like
this:

serial { mouse device /dev/cua0 }
serial { modem device /dev/ttypf }

Of course, the first of these lines should be adapted to your needs (but
not left out). The second line is the important part! This assumes that
you never use 15 pseudo-terminals at the same time. If this isn't true
for your situation (e.g. many users logged in over the net at the same
time), use some higher numbered pseudo terminal here and in step 9, but
for any usual configuration, ttypf will do.

5. Under dosemu, extract ethersl.com from the packet driver collection.
I propose to put this file into the root directory of your dosemu boot
disk.

Also, from SOSS extract the files soss.exe, custom.exe, netdev.sys, and
export.us. I propose to put them in C:\SOSS.

6. Under dosemu, change into C:\SOSS. Now execute "custom netdev.sys".
Choose "s" for "site configuration".
Now set (a) IP address to 192.0.2.2.
Setup (r) name servers by deleting all of them.
Set (s) subnet bits to 0.
I assume that the other settings don't matter, but if you have problems,
they might be a possible reason.
Go back (ESC) to the main menu.
I again just assume that the hardware settings are ignored, as we will
use a packet driver instead of direct hardware access.
Choose (e) exit and save.

7. Edit the CONFIG.SYS file to contain the line
DEVICE=C:\SOSS\NETDEV.SYS,

edit AUTOEXEC.BAT to contain:
ETHERSL 0x7e 3 0x2f8 19200,

edit C:\SOSS\EXPORT.US to contain a list of drives you want to access
from Linux.
Shutdown dosemu. (It must be restarted before you can use SOSS.)

Now the preparations are completed. To actually run and access SOSS, do
this:

8. In one virtual console start dosemu. Go to C:\SOSS and start SOSS (no
parameters required).

9. In a second virtual console, run as root
slattach -p slip -s 19200 /dev/ptypf,
this console will remain occupied by slattach.

10. In a third virtual console, do as root:
ifconfig sl0 192.0.2.1 pointopoint 192.0.2.2 mtu 1500
route add 192.0.2.2

Mount the SOSS drives, e.g.:
mount -t nfs 192.0.2.2:/c /dosC

Now this console can be used again for other purposes.

You should be able to use the SOSS drives now.

11. To shut down:
Unmount the SOSS drives, then just stop SOSS with ctrl-c, exit dosemu,
stop slattach with ctrl-c. 

Remarks:

(a) This example uses IP addresses that to the best of my knowledge are
available for testing purposes etc., you shouldn't use them if you want
to access SOSS from other machines. But that isn't necessary, as you can
mount the drives on the Linux machine and then mount them per NFS on
other machines from the Linux machine.

Generally this setup results in two completely independent Internet
nodes just happening to run on the same CPU. You have to configure it
exactly the same way as if you have a real DOS PC connected to your
Linux machine with a real SLIP line. That means either using an
dedicated subnetwork for the SLIP link or using proxy ARP.

(b) If you shut down and restart dosemu, you have to restart slattach
and to redo the route command as well, and vice versa. This is not
necessary if you interrupt and restart SOSS without leaving dosemu.

(c) I have left out timezone configuration, as I don't know exactly how
it should work (timezone option in CUSTOM, or SOSS interpreting the TZ
variable). If you want to get it right, please read the docs, try it,
and tell me how it really works.

Any comments and corrections (especially from SOSS experts) are welcome.

        Johannes

/s

Corey Sweeney
[email-masked]