[comp.os.minix] proposal for remote fileserver to access unix files in minix

jchvr@ihlpg.ATT.COM (Hartong) (07/07/87)

I just finished reading the book and have been bitten by the Mninx bug. 
I think Andy was very good in writing this book because he has led me
to think about the following (which I am sure he intended me to). 

Lets assume for now that via the COM1 port of our PC, the machine is
hooked up to a modem and logged into a standard Unix system. Would it
not be nice to have access via this small line to ALL files on the Unix system
(eg. to consider Unix as a remote file server for Minx). If we could make
this work then we could use the "host" as backup and as a very large (but slow)
disk!

How do we do this? Well for a start we must write a little program on Unix that
understand the 25 or so messages that Minix can send to FS. (eg. access, mdir,
chmod, ...) All this will be very simple on a Unix machine (I mean just look
at it closely!!).

The second step is to provide some lower level of communication between his
process on Unix and the FS on Minix. (we could use some kind a simplified 
kermit protocol).

The third step is then to hack the FS on Minix to transfer certain messages
to the Unix file server process while doing others still itself.

The fourth step would be to hack the mount system call to allow a user
to initiate the existence of the file server on Unix.

Did I arouse anyone interest enough to start a little discussion and maybe 
someone will start coding it?

H.F. van Rietschote

doug@marque.UUCP (harris) (07/08/87)

In article <3421@ihlpg.ATT.COM> jchvr@ihlpg.ATT.COM (Hartong) suggests:
>
>(eg. to consider Unix as a remote file server for Minx). If we could make
>
>How do we do this? Well for a start we must write a little program on Unix that
>understand the 25 or so messages that Minix can send to FS. (eg. access, mdir,
>chmod, ...) All this will be very simple on a Unix machine
>
>The second step is to provide some lower level of communication between his
>process on Unix and the FS on Minix.
>Did I arouse anyone interest enough to start a little discussion and maybe 
>someone will start coding it?

This idea is very reasonable, as is also the idea to use Ethernet or Starlan
interfaces that might exist on the PC.  I would strongly recommend that
anyone who is considering this option look at a "companion" book to
Andy T's O.S. book, namely, the second volume of Doug Comer's "Xinu"
book (Operating System Design, Volume II, Internetworking with XINU,
also a PH book, ISBN 0-13-637414-X 025).  This text relates the DOD
family of protocols, especially IP/UDP, to Xinu, and contains discussion
and implementation code for precisely the above suggested type of file
server; namely, a Unix file server for Xinu.  This runs over (more or
less) a UDP port, and the TCP/IP SLIP protocol could be adapted as the
protocol underneath UDP.  Even if you go with another protocol, the
discussion of naming conventions and so on for remote file systems is
well worth reading.

I expect next spring (soon enough :--) to have a class busily working
on a similar problem.  Of course if some of you implement it first
they will busily work upon modifying your code!

(For those who might not know, Xinu is a "simplified" Unix, also for
instructional purposes, discussed in Comer's first book by the same
title.  A discussion of Minix vs Xinu was held earlier in this group).

andrew@mulga.oz (Andrew Worsley) (07/08/87)

in article <3421@ihlpg.ATT.COM>, jchvr@ihlpg.ATT.COM (Hartong) says:
> 
> Lets assume for now that via the COM1 port of our PC, the machine is
> hooked up to a modem and logged into a standard Unix system. Would it
> not be nice to have access via this small line to ALL files on the Unix system
> (eg. to consider Unix as a remote file server for Minx). If we could make
> this work then we could use the "host" as backup and as a very large (but slow)
> disk!
> 
> H.F. van Rietschote

Douglas Comer has written a book "XINU II : Networking " in which he gives some
code for a remote fileserver for his XINU network. From memory it looked not to
hard to put in other operating systems (just the file serving part). It also
has a good discussion of the advantages of stateless fileservers. 

  I don't think a serial line is fast enough for fileserving, you need
something like an ethernet. TCP/IP is available (source code and all) as PC/IP
for the PC and there are several suitable boards on the market about
(Aus) $1000+. This would make a suitable basis for a fileserver, anyone got
the sources to NFS :-)

   We are looking at putting the PC/IP software into minix, possible as yet
another process, and I believe some of the authors of PC/IP have already
mentioned an interest in the area.

   These are just ideas at the moment, no one has anytime to do any of this
interesting work here. But it is an interesting idea, fileserving the PCs, the
poor mans Suns :-)


			Andrew W.

SWG.LPRESS@c.isi.edu (Laurence I. Press) (07/17/87)

Is there some automatic way that MINIX messages could be gathered
up and put in an unedited digest?  They are cluttering my mail.
Thanks,
Lar
-------

galvin@UDEL.EDU (James M Galvin) (07/17/87)

> Is there some automatic way that MINIX messages could be gathered
> up and put in an unedited digest?  They are cluttering my mail.

Sorry, that requires a volunteer with time, which I don't have.

Jim

gnu@hoptoad.uucp (John Gilmore) (07/21/87)

SWG.LPRESS@c.isi.edu (Laurence I. Press) wrote:
> Is there some automatic way that MINIX messages could be gathered
> up and put in an unedited digest?  They are cluttering my mail.

The moderator thought this would require human effort and declined.
However, the Usenet newsgroup "comp.os.minix" is available on the Internet
via NNTP.  This contains all the messages from the mailing list, which
you can read when YOU choose to rather than having them dumped in your
mailbox.  There are NNTP clients for Unix (rrn) and for several other
systems, I think including Lisp Machines and Tops-20.  Contact Erik Fair
(fair@berkeley.edu) for more information.
-- 
{dasys1,ncoast,well,sun,ihnp4}!hoptoad!gnu	     gnu@postgres.berkeley.edu
Alt.all: the alternative radio of the Usenet.