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Re: cfdisk vs fdisk & speaking of Western Digital drives...



hi ya andy

On Sat, 3 Jan 2004, Andy Firman wrote:

> First, what is the difference between fdisk and cfdisk,
> other cfdisk being curses based?

imho, fdisk is more controllable of what it does ... 
 
> I partioned both disk's exactly the same using cfdisk 
> during the install.  It seems that one drive has 4863 cylinders
> and the other has 77545 cylinders.  Why would Western Digital
> make the drives different?  Or did I do something wrong 
> with partitioning/formatting?

its a problem of mapping the chs to the proper number of heads
( 16 or 255 ) ... and seems to depend on mb (bios) and ide cables
and ide controllers
	- some cables have that "hole" .. some dont ...
	- some drives like to be cable select others dont 
	- some bios like to use 16 heads for hda and 255 for hdb (dumb)

	use hda and hdc or hdd whichever gives the right number of
	heads ...

	if fdisk shows the two identical drives as different
	number or partitions,  do the partitioning twice 

	- partition disk1  on /dev/hda

	- power off ...

	- partition disk2  also as the new /dev/hda 

	now use the identically partitioned disk as /dev/hda and /dev/hdc
	and everything should be happy

if the partition table (number of cylinders/heads ) is different,
it doesnt matter too much ... just makes things messy ...
and the asumptions is that raid sw wont have any problems jumping around
to the right sector that is physically different on each disk
	- best to keep the same number of cylinders, heads on both disks

c ya
alvin

> cfdisk /dev/hda 
>            Heads: 255   Sectors per Track: 63   Cylinders: 4863

see the number of heads

> cfdisk /dev/hdd
>            Heads: 16   Sectors per Track: 63   Cylinders: 77545

see the numbver of head

you want for performance, for both disks to look identical c/h wise



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