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Re: Help(!) with Slink install -- disk repartitioning problem

Hai Chris,

> info on large disc problem snipped

I'm no HD-guru, actually no guru at all, but I think I've dealt with a
similar problem here, so...

I think you hit the 8Gig limit. Older BIOSses can't cope with large disks
(they won't pass the correct info onto the OS or something to that effect),
but linux can cope, once told the size and the geometry of the disc. 
Here are the steps I took (but please do read the Large-Disc-HOWTO):

1: Look up the LBA geometry your BIOS tells the disc has
2: pass this info to any Linux kernel used

step 2 is a little tricky in that the install allready uses a linux kernel.
IIRC the install starts with a boot line, at which you can type in a
different kernel or any kernel parameters. type here something like:

   boot: linux hda=1826,255,63

(use different numbers, those worked for my 15Gig drive!!!)

and after install you should add to /etc/lilo.conf a line like

append="hda=1826,255,63"  #again, change the numbers!!!!!!!!

run lilo, and all should be fine, I hope

> We went into the BIOS setup, and checked the disk information from
> there.  Here is what it reported about the drive:
> 	Cylinders	 17475
> 	Heads		    15
> 	Sectors		    63
> 	Max Capacity	  8455 MB
> 	   LBA Format

the LBA format line should give you Cyls/heads/secs numbers too, use those.
if you can't find those, I guess you could calculate your own

> I don't know much about hard drives, and don't really know what LBA
> is, but the apparent loss of disk capacity seems somewhat similar to
> the difference in capacity between the two "Max Capacity" lines
> listed.  Is the second capacity somehow illusory, or available to DOS
> but not Linux?

no it's real, on LBA: look it up in the Large-Disc-HOWTO

> After I set up partitions for Linux to use as much disk as fdisk would
> let me, fdisk reports the following:
>         Disk 240 heads, 63 sectors, 1024 cylinders
>         Units = cylinders of 15120 x 512 bytes
>         Device    Boot  Start  End  Blocks  ID  Sys
>         /dev/hda1   *     38   824  594XXXX  c  Win95 FAT32 (LBA)
>         /dev/hda2          1    37   28XXXX a0  Unknown [laptop suspend part.]
>         /dev/hda3        825   842   136080 82  Linux Swap
>         /dev/hda4        843  1024  137XXXX 93  Linux native
>         [X's fill in the digits I didn't copy to my notepad]
> Note that the disk geometry is totally different than what was listed
> from the BIOS -- I don't know if this is meaningful, or related to the
> apparently-missing disk space.  Does fdisk always assume a maximum of

it is exactly the missing area!

> 1024 cylinders?  Should I use the expert mode of fdisk to manually
> supply the disk geometry information from the BIOS and then re-make

yes, but not necessary once you've told the kernel at boot time the
geometry to use. Be carefull though, the kernel doesn't check it, so
any errors in the geometry might destroy your harddisk!

> the Linux partitions, or will this totally destroy the data currently
> on the disk (in the Win95 partition)?

not if you use the proper geometry:)

groetjes, carel

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