The power of cloud storage, for DOS!
News
- 2026-04-10: A faster version of NetDrive is available for testing. Jump to "Testing" and help me ensure it is the best it can be.
(Want to jump straight to the demonstration video? See it at mTCP NetDrive Demo.)
NetDrive is a DOS device driver that allows you to access a remote disk image hosted by another machine as though it was a local device with an assigned drive letter. The remote disk image can be a floppy disk image or a hard drive image.
Use it to:
- Add temporary extra space to a DOS machine.
- Mount your library of floppy images directly on your DOS machine.
- Create a repository of utilities or files that all of your DOS machines can share.
- Provide a quick and easy backup target for Xcopy or Zip.
- Add hard drive-like storage to machines that don't have a hard drive.
- Create public file repositories for DOS users.
There are plenty of other programs for accessing remote data available. Here is the quick list of things that makes mTCP NetDrive interesting:
- A single device driver works with all versions of DOS starting with DOS 2.0.
- The device driver uses less than 6KB of RAM. (Add another 5 to 10kB depending on your Ethernet card.)
- DOS 3.31 and up can use remote images up to 2GB in size. (Earlier versions of DOS are limited to 32 MB because they use FAT12 or original FAT16.)
- The server runs on Windows (10 or 11) or Linux. No special permissions are needed.
- The protocol uses UDP so you can use it on your private network or across the Internet.
- Network drives are standard raw disk images that can be manipulated using Linux tools.
- Multiple remote drives from different servers can be mounted at the same time.
- "Undo support": Use the checkpoint feature to undo accidents or changes! Right from the DOS command line!
If you use mTCP today it is as simple as installing the device driver and then running a command line program to attach or detach the remote storage.
Download
mTCP NetDrive is now included with the rest of the mTCP programs. See the main mTCP page for downloads:
- The DOS device driver and command line utility are packaged with the rest of mTCP.
- The servers (Linux, Windows, Mac, etc.) are in a separate download.
- The mTCP documentation PDF covers both the DOS device driver and servers.
Public test server - try it out!
Try the magic of using a DOS drive letter across the internet! The following disk images are available: (All image names are case sensitive and are lower case.)
| Hard drive images | ||
| fat12.dsk | 32MB FAT12 hard drive image suitable for DOS 2.0 and up. DOS utilities and RLE files. | |
| bigdisk.dsk | 200MB FAT16B image suitable for Compaq DOS 3.31 or MS-DOS 4.0 and up. DOS utilities, RLE graphics, shareware games, etc. | |
| hugedisk.dsk | 2GB FAT16B hard drive image suitable for DOS 3.31 and up. Mostly empty but it works. | |
| Floppy images | ||
| ibm_dos_11.dsk | IBM DOS 1.1 on the original 160KB diskette. | |
| buick_1.dsk and buick_2.dsk | Buick demo diskettes from the late 1980s. | |
| pcmag_march_1988.dsk | PC Magazine shareware/utility diskette from March 1988. | |
Assuming you have the device driver installed, mTCP is configured, and your NetDrive drive letter is D: this command will connect you to the 200MB disk image listed above:
netdrive connect brutman.com:2002 bigdisk.dsk d:
After that command runs, go to drive D: and play around. Do anything you want, including modifying or deleting files; your view of the files will change as needed but the server version will not be altered. And all of this is happening over the Internet!
Bigdisk.dsk is probably the most interesting, as it has a nice curated selection of utilities and software on it. Fat12.dsk is suitable for older systems that can't read FAT16 filesystems. Hugedisk.dsk is just to show that it works up to 2GB. The floppy images are there for variety but don't try to run anything from the IBM DOS 1.1 diskette as those programs are not compatible with any modern DOS. (It's there to demonstrate that NetDrive can handle the more unusual formats.)
Depending on where you are in the world access to these will be slow but usable, so please be patient! The server is located in the middle of the US and the round-trip time between you and the server directly impacts the performance. A server in your own home or being in the same region as the server makes things infinitely faster.
All of these images will appear writable to you, so you can play games and update high-score files, run benchmarks (including write speed testing), or just mess around. Your changes will only last for the duration of the session; when you disconnect the changes are lost. (The server has the "session scoped writes" feature described above turned on.) To keep the server from running out of space there is a maximum number of writes allowed per session, a maximum session length, and a timeout timer.
Help test a faster version!
2026-04-10 I have an experimental version of the NetDrive device driver and server that I need more help testing. This version is *far* faster when connecting to servers over the internet that are not in your region, but even on a local LAN you might see some improvement in the speed of the connection.
If you want a glimpse of the future and enjoy some faster speeds, please download and install the new code. You will need both the DOS and server code. The links are:
- https://www.brutman.com/mTCP/download/mTCP_NetDrive_2026-04-09_DOS.zip
- https://www.brutman.com/mTCP/download/mTCP_NetDrive_server-bin_2026-04-09.zip
The new DOS code will not work with existing servers but older, non-experimental DOS code will work with the new servers so it is safe to update your personal servers. The public server at brutman.com listed above is also on the new version of the server if you want to test a remote server and see the speed increase.
Slower machines will not see as much of a benefit, as they might barely be keeping up with packet processing. But even an XT connecting to a remote server saw more than 2x improvement when reading and more than a 3x improvement when writing.
Don't forget to send me an email and let me know how it worked for you! And thanks in advance!
Created December 10th, 2023, Last updated April 10th, 2026
(C)opyright Michael B. Brutman, mbbrutman at gmail.com