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Can't Format "Network" Drive to do Install

From C C on Thu, 23 Mar 2000

I have 2 hd,s. One windows 95 and 1 linux mandrake 6.0 using lilo to access which system i want to use. linux has disappeared along with lilo at dos bootup. my system still lists 2 hard drives. i am trying to format my linux drive and reinstall it but dos says i cannot format my d drive because it is a network drive? I'm lost . I am not connected to a network. Any suggestions?

Thanks for any help,
Mr Grant

Do you have two physical hard drives, or two partitions (drive "letters")? IDE or SCSI? One interface/cable --- or two (different cables)?

Where does your system still lists two hard drives? In the CMOS setup? Using some sort of GUI filemanager? In FDISK.EXE?

What are you using attempt to format these drives? Command line utility? GUI tool? MS or some 3rd party, like Norton?

Why are you using any sort of MS DOS/Windows formatter to attempt preparation of a filesystem for installing Linux? What if you boot up a Linux installation utility and see what it says? (In particular, what does the Mandrake version of fdisk say about /dev/hda and /dev/hdb or /dev/hdc)? (Those device names are conventional for IDE drives; /dev/sda, /dev/sdb, etc are common for SCSI drives).

What do you mean "disappeared" and "along with lilo"? Do you mean that LILO used to work and now you don't see any LILO prompt or messages when you power up the system?

At a guess it sounds like some Microsoft upgrade, patch or utility that you installed or ran overwrote your MBR (master boot record) code and/or partition table. The MBR is the first accessible sector on a hard disk. The MBR on the first hard disk in a system hold's the system's boot code or "boot loader."

This is a very small bit executable code (usually written in assembly language --- less than 466 bytes long) which finds, loads and executes the rest of any operating system. Every operating system comes with its own boot loader, but many boot loaders can be configured to load multiple different operating systems. Linux offers a number of different boot loaders --- LILO is the most common one on the PC. Another would be GRUB (the GNU "grand unified boot loader").

Microsoft's boot loader isn't very flexible nor it is at all smart. It simply looks for the "active" partition, loads the first sector of that (the logical boot record) and executes whatever is there). Usually this is a secondary boot loader for DOS or Win '9x. Often it is a virus (a traditional boot sector virus --- not a new-fangled multi-partite MBR infector!). Sometimes that might be a copy of their "Boot Manager" --- from OS/2, later NT. "Boot Manager" is a fairly fat secondary boot loader, it takes up a small partition of its own (minimum 1 Meg.? --- my whole kernel image fits that).

Microsft OS products and utilities have an ongoing and egregious predilection for overwriting the boot loaders (sometimes even the partitions) of other operating systems. One might think they they didn't what you installing anything else on THEIR systems.

The good news is that you data and filesystems are probably still there. If you get a technically inclined friend to visit you (or call a commercial support line, like the one I work for) to show you how to run fdisk (the Linux version) and how to interpret it's listings then we might be able to "rescue" your Linux files and settings. Even if the partition table was overwritten it is likely that the filesystem(s) is/are still there in portions of the disk(s) that appear to be "unused" (as far as DOS/Win '9x is concerned).

There is a tool called "gpart" which can scan a disk looking for partition signatures, which can often help rebuild a damaged or lost partition table. This is a fairly advanced trick; something I don't have time to write up again here. I've described it before --- though even then it might entail a bit too much background explanation for you at this point.

Of course, if you don't have any data or settings on the "missing" copy of Linux that you're interested in recovering, then it will be much easier and cheaper for you to simply re-install Linux.

I presume that you got it installed before. If someone else did it for you --- have them come back and show you how (or just give it a go on your own. The Mandrake and Macmillan manuals aren't too scary).

After you've either recovered or re-installed your Linux system, remember to create a boot/rescue disk for it. Also create a small file (recover.mbr) using a command like:

dd count=1 bs=512 if=/dev/hda of=/tmp/recover.mbr

... this will create a small (512 byte) file in your /tmp that you can copy onto your boot/rescue floppy. That way, the next time this happens to you you can boot from your rescue floppy, and using a command like:

dd count=1 bs=512 of=/dev/hda if=/tmp/recover.mbr

(all I did was exchange the if= and of= parameters by changing an i to an o and vice versa, that reverses the direction of this "data dump" command making the input file into the output file and vice versa).

If you need to get a rescue floppy take a look at Tom's Root/Boot (http://www.toms.net/rb) Not only does Tom Oehser provide the coolest rescue floppy around, he also has links on his web site to many other cool "floppy-based" Linux distributions. In addition, if you get to a local Linux users group you might pick up a copy of the Linuxcare "bootable business card"

(The BBC is a business card sized CD-ROM "disc" which my employer puts together to give away at trade shows and to donate to users groups for their members and door prizes --- it has about 50Mb of handy utilities) --- we're trying to clean the underlying sources and make files enough to publish so others can build their own BBC (you can already download the ISO image and burn it onto your ISO image --- go to http://www.linuxcare.com/bootable_cd for more info).

Hopefully that will help. If you can't wipe MS completely off you hard drive, and you get those programmers in Redmond to write well-behaved code that respects your other OS' on YOUR computer --- at least you can get the tools to take control of your PC (and learn how to use them).

Where did it go

From A & C Costa on 24 Mar 00

Hey Guy,
I really appreciate you taking the time to get back to me so fast. I will look into your suggestions and will let you know how I make out.
Thanks Again

Mr Grant

Copyright © 2000, James T. Dennis
Published in The Linux Gazette Issue 52 April 2000

HTML transformation by Heather Stern of Tuxtops, Inc., http://www.tuxtops.com/

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