====== Working with software RAID  ======

see also: 
   * [[http://gentoo-wiki.com/HOWTO_Gentoo_Install_on_Software_RAID|Gentoo Howto on RAID]]
   * [[http://www.debian-administration.org/articles/424|growing ext3 partition on RAID1 without rebooting]]
   * [[:linux:lvm|LVM]]


===== Debian Woody + kernel 2.4 =====

Good article (based on the one that has already been available on TNT) on this topic is on URL: [[http://www.rot13.org/~dpavlin/md-raid1.html]]

===== Debian Sarge  =====

TODO

===== sw RAID recover =====
**Copying the partition table from working HDD to new one**

   sfdisk -d /dev/sda > /tmp/partions
   sfdisk --force /dev/sdb < /tmp/partions 

**Adding partitions back to raid**
   mdadm -add /dev/md0 /dev/sdb1
   mdadm -add /dev/md1 /dev/sdb2
   mdadm -add /dev/md2 /dev/sdb3
   mdadm -add /dev/md3 /dev/sdb4

===== Force the Linux kernel to re-read a partitiontable =====

   blockdev --rereadpt /dev/device
<note warning>**Do NOT do this on a device where filesystems are mounted from.**</note>

===== Boot system with GRUB from RAID1 =====
see also: [[http://www.texsoft.it/index.php?c=hardware&m=hw.storage.grubraid1&l=it|Very detailed instalation of fedora4]], [[http://ruslug.rutgers.edu/~mcgrof/grub-images/|GRUB Splash Image Howto]]
   [root@fedora4 ~]# grub
   
       GNU GRUB  version 0.95  (640K lower / 3072K upper memory)
   
    [ Minimal BASH-like line editing is supported.  For the first word, TAB 
      lists possible command completions.  Anywhere else TAB lists the possible
      completions of a device/filename.]
  
   grub> root (hd0,0)
    Filesystem type is ext2fs, partition type 0xfd
   
   grub> setup (hd0)
    Checking if "/boot/grub/stage1" exists... yes
    Checking if "/boot/grub/stage2" exists... yes
    Checking if "/boot/grub/e2fs_stage1_5" exists... yes
    Running "embed /boot/grub/e2fs_stage1_5 (hd0)"...  15 sectors are embedded.
   succeeded
    Running "install /boot/grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/boot/grub/stage2
   /boot/grub/grub.conf"... succeeded
   Done.
   
   grub> root (hd1,0)
    Filesystem type is ext2fs, partition type 0xfd
   
   grub> setup (hd1)
    Checking if "/boot/grub/stage1" exists... yes
    Checking if "/boot/grub/stage2" exists... yes
    Checking if "/boot/grub/e2fs_stage1_5" exists... yes
    Running "embed /boot/grub/e2fs_stage1_5 (hd1)"...  15 sectors are embedded.
   succeeded
   Running "install /boot/grub/stage1 (hd1) (hd1)1+15 p (hd1,0)/boot/grub/stage2
   /boot/grub/grub.conf"... succeeded
  Done.
   
  grub> quit