bkc@CLUTX.CLARKSON.EDU (Brad Clements) (01/06/88)
Help! I am looking for a program(s) that will redirect MS-DOS file I/O commands to another system such as unix. I have heard that there is a system somewhere called Remote Virtual Disk (RVD) that allows a user to map an MS-DOS disk drive to the root of a remote Unix system. Does anyone know where I can find this software or something that does the same thing? Please reply to Brad Clements bkc@clutx.clarkson.edu bkc@clutx.bitnet Thanks!
JBVB@AI.AI.MIT.EDU ("James B. VanBokkelen") (01/06/88)
That is the name of a protocol included in the MIT PC-IP distribution. It allows creation of virtual DOS volumes on Unix systems, but 1) it doesn't allow read/write sharing of those volumes, and 2) it requires Unix source code and kernel modifications to install. I've never used it on a PC, but I've used Unices sharing disks via the same protocol, and there were some unloveable aspects about spinup-spindown... I don't know how you get the source for the Unix side. I'd start with the contact for PC-IP at MIT (the Microcomputer Office), and see if they can help/redirect you. jbvb
mcc@ETN-WLV.EATON.COM (Merton Campbell Crockett) (01/06/88)
Brad:
Softronics offers a product called Softerm PC which includes a "seamless disk"
or "remote virtual disk" capability. In release 2.00.09 of the software, I
was able to access the disk on our DDN gateway VAX running bsd 4.3. They
were some problems with the implementation:
1. The procedure that you create for the "seamless disk" had to log
you in to the correct account on the host system. (MS-DOS wanted
to interpret the "/" in the UNIX path name as a MS-DOS switch.)
2. The files name had to follow MS-DOS naming conventions and file
name length restrictions.
3. The file name had to be all upper case characters unless you used
the UNIX upper/lower case translation capability by logging in
using upper case characters in which case you could access files
with lower case names.
I currently use release 2.10.02 but haven't gotten around to retesting to
see if they corrected the above problems.
Merton Campbell Crockettsnorthc@NSWC-OAS.ARPA (01/06/88)
I looked into RVD several months ago. It is a large [code size] system that does not appear to be in production use anywhere (rumored to still be used in a UNIX host - UNIX host fashion at its birthplace, MIT). I would suggest you consider one of the following commercial products: NFS; NetBios/TCP; Locus "DOS Merge". (If my job depended on making the best choice I would choose NFS, if you want the choice with the most future/potential choose NetBIOS/TCP) Best of luck, let us know how you work your problem out, Stephen Northcutt (snorthc@nswc-g.arpa) Caveat: I have been looking at the problem you describe for several months and am not completely satisfied with any of the alternatives.
mcc@ETN-WLV.EATON.COM (Merton Campbell Crockett) (01/06/88)
Brad: I forgot to mention in the previous missive that Softerm PC does not support any of the TCP/IP suite of protocols but you do have your choice of 1. Crosstalk 2. Hayes-verify 3. Kermit 4. Softrans 5. Xmodem 6 Xmodem-CRC Softrans is a Softronics home-brew file transfer protocol with an encoding algorithm which allows you to transfer 8 bit binary data over links which only support 7 bit data transfers. (They include source for Softrans so that you can adapt it to your host system). Merton Campbell Crockett
nowicki@SUN.COM (Bill Nowicki) (01/07/88)
I am looking for a program(s) that will redirect MS-DOS file I/O commands to another system such as unix. Why not use PC-NFS? Just call 1-800-334-SUNM (1-800-334-7866) and give them Master Card or Visa, and it will be shipped in 48 hours.
larry@sbo.UUCP (Larry Mullen) (01/08/88)
We also market a product to provide a virtual disk for PCs. The name is PC Interface. It supports multiple PCs over RS232, or LAN under tcp/ip, or xns. It will allow the PC users to set up multiple virtual disks on our Unix system, based on a Unix login and password. Users can also use the PCs as virtual terminals. Apparently, it was developed by Locus, but part of it must be ported to the Unix which you connect to. Larry Mullen ...mot!nud!sbo!larry
ROMKEY@XX.LCS.MIT.EDU (John Romkey) (01/08/88)
A recent message contained some disinformation about RVD. RVD is the Remote Virtual Disk protocol, which was designed and implemented at the MIT Lab for Computer Science several years ago. It is a DISK sharing protocol rather than a FILE sharing protocol. It sends requests to a server for reading and writing disk blocks by offset into the disk. Because it is a disk sharing protocol, it sits below the filesystem, so although you could share a disk between a UNIX and an MS-DOS system, it wouldn't be useful because there would either be a UNIX or an MS-DOS filesystem on that disk that one of the two systems wouldn't understand. RVD was originally written for 4.2BSD. The VAXen at LCS all had small disks (RK07's) and we wanted to have some disk servers to share things like UNIX which didn't change very often, and to have some large private disks for individual projects. RVD doesn't provide any synchronization between disk accesses. Since synchronization would really have to occur at a filesystem level and RVD is below the filesystem, this is fairly reasonable. RVD allowed disks to be accessed as read only or read write (shared or exclusive). Nobody ever wrote the companion synchronization protocol that would be needed to allow multiple writers, so we never used it in this mode. Also, RVD was never a part of PC/IP. I wrote a PC/IP RVD client as a hack, and a few people around LCS started using it. But we never got RVD packaged up and stabilized as much as we felt was necessary in order to include it in PC/IP, largely because of all the UNIX modications that were necessary. There were some references to it in the PC/IP documentation, though. I don't believe that MIT ever had an 'official' release of RVD, though a few copies were slipped to people. Anyway, RVD is not useful for sharing filesystems between UNIX and MS-DOS because it's a disk protocol and not a file protocol, and because it wouldn't allow multiple writers. To get back to the desired goal, I would recommend one of two approaches: NFS - currently only available from Sun or SMB over NETBIOS - put up a NETBIOS SMB server on the UNIX system and get NETBIOS for the PC and run the PC LAN program. NETBIOS for the PC is available from many vendors and there are a few people out there working on it for UNIX (try Syntax). - john romkey -------