Re: RAID

[Alvin Oga <aoga@mail.Linux-Consulting.com>]

On Mon, 10 Oct 2005, Bogdan Rotariu wrote:

>   I have 3 hard disk at 250GB SATA 150 mounted on a RAID adapter.
>   Because the adaptor makes me a lot of problems, i whant to use a
>   software RAID 5.

with 3 disks .. you're wasting 33% of usable disk in raid5
with 4 disks .. you're wasting 25% of usable disk in raid5

- the data better be worth the extra $$$ due to disk dying

>   I download the netinstal iso of sarge and when i must choise the way
>   of partitioning the hard drives, the partition utility give me some
>   errors. I create on every hard disk a primary RAID partition and i
>   create a RAID 5 md device.

good .. assuming you did what i think you did..
	- "FD" partition type for each partiton that will be
	used in sw raid

>   The problems apear when i must partition this hard disk, because the
>   installer makes me just a partition and after that, it tells me that
>   i can't create another partition because there are to many primary
>   partition. 

you can only have 3 primary partition and one extended partition
or up to  4 primary partitions

you can have as many logical partitions in the extended partition
as you like

if the differences betwween primary and extended and logical partitions
is like an alphabet soup..
	- you should use extended partition type for partition#4
	and do everything else as you normally did before 
	( following the defaults fdisk/cfdisk gives you )

	- other options is to use 4 or less partitions, but that
	is bad idea, extreme bad idea in my book

c ya
alvin