LINK : http://home.gagme.com/greg/linux/raid-lvm.php#overview

0/ utworzyc partycje typu fd ( Linux raid autodetect ) na dyskach ktore 
   chcemy uzyc do raida , u mnie byly to :
	/dev/sdc
	/dev/sdd

1/ create array :

mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/sdc1 /dev/sdd1

OUTPUT :
mdadm: chunk size defaults to 64K
mdadm: /dev/sdc1 appears to contain an ext2fs file system
    size=390708800K  mtime=Thu Jan  1 01:00:00 1970
mdadm: /dev/sdd1 appears to contain an ext2fs file system
    size=390708800K  mtime=Thu Jan  1 01:00:00 1970
Continue creating array? y
mdadm: array /dev/md0 started.

[root@heplx42 etc]# cat /etc/mdadm.conf
ARRAY /dev/md0 level=raid0 num-devices=2
UUID=dbb195ab:782458bf:1be29c36:8efdc90b
   devices=/dev/sdc1,/dev/sdd1
[root@heplx42 etc]#

[root@heplx42 etc]# cat /etc/mdadm.conf
ARRAY /dev/md0 level=raid0 num-devices=2
UUID=dbb195ab:782458bf:1be29c36:8efdc90b
   devices=/dev/sdc1,/dev/sdd1
[root@heplx42 etc]# cat /proc/mdstat
Personalities : [raid0]
md0 : active raid0 sdd1[1] sdc1[0]
      781417472 blocks 64k chunks
       
unused devices: <none>
[root@heplx42 etc]#


[root@heplx42 etc]# mdadm --detail /dev/md0
/dev/md0:
        Version : 00.90.01
  Creation Time : Tue Apr 11 12:27:31 2006
     Raid Level : raid0
     Array Size : 781417472 (745.22 GiB 800.17 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0
    Persistence : Superblock is persistent
 
    Update Time : Tue Apr 11 12:27:31 2006
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
 
     Chunk Size : 64K
 
           UUID : dbb195ab:782458bf:1be29c36:8efdc90b
         Events : 0.1
 
    Number   Major   Minor   RaidDevice State
       0       8       33        0      active sync   /dev/sdc1
       1       8       49        1      active sync   /dev/sdd1
[root@heplx42 etc]#


lub :

mdadm --create --verbose /dev/md0 --chunk=64 --level=raid0 --raid-devices=2 /dev/sdc1 /dev/sdd1


2/ logical volume creation :

	a/ initialize a disk or parition for use by LVM
		pvcreate /dev/md0
	b/ vgcreate will then create the Volume Group, in my case I called it lvm-raid
		vgcreate lvm-raid /dev/md0
	c/ zobaczyc rozmiar :
		vgdisplay lvm-raid
	d/ lvcreate -l 190775 lvm-raid -n lvm0 
	e/ lvdisplay /dev/lvm-raid/lvm0 

3/ mkfs /dev/lvm-raid/lvm0 -t ext3
   mount 

i gotowe !