Best of Technical Support

Our experts answer your technical questions.
Mounting NFS

I need to implement NFS (Network File System) from my Linux host to a WinNT Server for files access. I have Linux Red Hat 5.2 installed on a Pentium 133 MHz and 24MB RAM machine. I also installed the NFS services (client and server). In a server machine, I have Windows NT 4.0. I read the book TCP/IP Illustrated Vol.1 by Richard Stevens (chapter 29 talks about NFS), so I am a beginner of the protocol. When I try to mount an NFS link, the following error appears:

mount: RPC: Port mapper failure - RPC: Unable to send

Can you help me? —Ing. Juan Salazar Velasco,

The easiest way to do this is not with NFS, but with Samba, which you can get at By installing Samba on your Linux box, you will be able to use smbclient to access your Windows NT server, and the combination of nmbd and smbd to allow your NT server to access files on your Linux box. This works for printers, too.

NFS services require special configuration in the Windows NT server (and usually additional software), and often aren't as fast because the native protocols to each type of server (SMB for NT and NFS for UNIX) were designed with somewhat different intentions in mind. In my experience, UNIX emulates SMB better than NT emulates NFS. —Chad Robinson,

It's not clear to me which machine is the NFS server. If it's Linux, then most likely the portmapper isn't running. Type:

/etc/rc.d/init.d/portmap restart

Also, make sure that rpc.nfsd and rpc.mountd are running on your machine.

If the server is NT, type:

showmount -e name_of_nt_server

and as long as you don't get suitable output from it, your NT server isn't configured correctly. —Marc Merlin,

Hard Drive Problems

While trying to install Linux 5.2 from the Linux For Dummies book, I have somehow locked myself and the install program out of it. Once you have partitioned a drive partially for Linux, how do you get back in and straighten out any mess you may have made? The install floppy or the CD-ROM have nothing on them that I can access from the DOS prompt or from the DOS program fdisk, which, by the way, says there is an error reading the disk and won't let me in. Also, DiskDruid won't let me back in either. Can you help? —“Budskie”,

I would guess that you somehow damaged your partition table, but this is tough to tell without looking further at the drive. You may wish to try a different tool, such as the fdisk program that comes with the Slackware package. It is a more raw tool, and while it may be harder to use, it probably won't completely stop you from getting to your drive.

I've seen problems like this come from misunderstandings about the LBA (logical block addressing) setting in the BIOS for a drive. Unfortunately, without knowing more about what exactly has happened, I can tell you only how to completely wipe out what you've done so you can reload your system. (The adage about backups comes to mind here.) If you do go this route, you would want to use a more basic tool (such as the fdisk that ships with Slackware) to remove all of the Linux partitions on your drive in the hopes of recovering your DOS information. Failing that, you could always remove them all and re-install Windows to return to a stable state, then try again. —Chad Robinson,


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