FDISK weirdness

[Dan Murphy]

I've got something going on with fdisk, and it looks like I need a little help.

First, some background. I installed Linux on one machine about a year ago, and it went very smoothly. It was a simple machine with a small HDD, no SCSI or CDROM, and no X installed, so it was uneventful.

Just got a new machine at work, and I hit a roadblock right away, but I'm sure it's a common one. Let me give the details on the machine, first:

Pentium 90
16 MB RAM
Mitsumi FX400 4X IDE CDROM
2 - WD Caviar 850 MB drives  (Model #AC2850)

I want to partition my second HDD in half, split between DOS and Linux.

The first time I did it:
1. Ran DOS FDISK and took first half of HDD
2. Booted Linux bootdisk
3. Ran fdisk for the Linux partition, but only ended up with about 80 MB!

It seems the disk didn't want to be any bigger than 512 KB.


Also, Linux doesn't like to be above cylinder 1023. So, I removed all the partitions, and redid things so that Linux was in the first half.

1. With no partitions defined, boot Linux & run fdisk
2. Define the Linux partion (410MB) and a 8MB swap partition
3. Also, define a DOS partition using Linux fdisk, because DOS FDISK yielded results similar to above
4. Boot DOS, run FDISK to see what it thinks. Here's what I get:

Partition    Type       MB     System    % Used
1           non-DOS    410                 81%
2           non-DOS     8                   2%
3           PRI DOS    395     FAT16       78%

Total disk space is 504 MB



Hmmmm. So, I start looking around for some Linux FAQs and HOWTOs and found a mini-HOWTO about Large IDE drives, which explains the problems with large drives, EIDE, addressing, DOS FDISK and Linux fdisk. The writer mentions that newer kernels don't have any problems with large IDE drives. He introduces a solution, but I'm not sure it will fix what I've got.

My BIOS has this definition of my drive:
1654 cyls, 16 hds, 63 sect

which disagrees with what the HOWTO said (it said the BIOS would have a bogus cyl count and head count.


Now, using DOS FDISK, I deleted all the partitions, and added a DOS partition to take the whole drive (just for hahas), and all it can take is 504 MB. A message during boot time says LBA has been turnrd off for that drive (still on for the first one, though), but when I go into BIOS setup, it says LBA is on.


Questions:

1. Is the way I have things partitioned now bogus? DOS thinks so.

2. Is there a right way?

3. Any other docs (HOWTOs, etc) to look at?


Thanks,

Dan "it was so easy the first time" Murphy


Dan Murphy                 murph at vmark.com
Vmark Software             74260.3322 at compuserve.com
Westboro, MA