Differences between revisions 1 and 21 (spanning 20 versions)
Revision 1 as of 2004-02-22 00:07:42
Size: 349
Editor: anonymous
Comment:
Revision 21 as of 2015-04-20 06:09:01
Size: 4342
Editor: ?PedroMacanas
Comment:
Deletions are marked like this. Additions are marked like this.
Line 1: Line 1:
## Auto-converted by kwiki2moinmoin v2005-10-07
There needs to be a method to install Debian onto a software RAID
mirror. This has been lacking for years it seems. Others have
figured it out, why hasn't Debian?
## page was renamed from DebianInstallerSoftwareRaidRoot
#language en
Line 6: Line 4:
Tools like mdadm and raidtools2 are out there. However the current
kernel-images don't even support having "/" on a ["RAID1"] mirror.
Lenny (5.0) and later support having the root and {{{/boot}}} partition on RAID volume. Actually, you can have root on RAID1+LVM partition.

This page contains some screenshots to demonstrate it, and applies to Debian 5.0 through, at least, 8.0.

== Root on software RAID+LVM ==
In this example, we use virtual machine ([[QEMU|qemu]] or [[KVM|kvm]])... we can play, and break them ;-)
 {{{
$ sudo apt-get install kvm

$ qemu-img create -f qcow2 hda.qcow2 4G
Formatting 'hda.qcow2', fmt=qcow2, size=4194304 kB

$ qemu-img create -f qcow2 hdb.qcow2 4G
Formatting 'hdb.qcow2', fmt=qcow2, size=4194304 kB

$ kvm -hda hda.qcow2 -hdb hdb.qcow2 -cdrom debian-lenny-i386-netinst.iso -boot d
}}}

Of course, you need to download a cdrom image.

==== Root on RAID+LVM example ====
Those few screenshots show how to install root on lvm on raid :

Once you have reach DebianInstaller partitioning screen...

Choose manual partitioning, then on each disk, manually create a partition (same size on both disks).

===== Create partitions for RAID =====
 * {{{Use as "Physical volume for Raid"}}} : <<BR>> {{attachment:00.gif}}

===== Configure RAID =====
 * We have a raid partition on each disk: <<BR>> {{attachment:01.gif}}
 * Choose the type of multidisk device to be created: <<BR>> {{attachment:02.gif}}
 * We have two partition: <<BR>> {{attachment:03.gif}}
 * (In this example, we have no spare partition).
 * Let's select the partitions to use: <<BR>> {{attachment:04.gif}}
 * That's it ! <<BR>> {{attachment:05.gif}}

===== Configure LVM =====
 * Let's configure the Logical volume manager: <<BR>> {{attachment:06.gif}}
 * First create a volume group: <<BR>> {{attachment:07.gif}}
 * Here, I chose the name ''vg1'' for the group: <<BR>> {{attachment:08.gif}}
 * We have only one raid device: <<BR>> {{attachment:09.gif}}
 * Let's create the ''logical volume'' (kind pf partitions): <<BR>> {{attachment:10.gif}}
 * Our Logical volume (LV) will use some disk space from ''vg1'' (which belongs to ''md0''): <<BR>> {{attachment:11.gif}}
 * I named my partition ''foobar_root'': <<BR>> {{attachment:12.gif}}
 * In this example, we wont split the filesystem (we won't even bother to create a swap, which is a bad idea), so I use all the disk space. (which again isn't a good idea, since it's so easy ro resize a partition with LVM) <<BR>> {{attachment:13.gif}}
 * Finish: <<BR>> {{attachment:14.gif}}

===== Use the LVM volumes =====
 * Let's assign and format the volumes (''partitions''): <<BR>> {{attachment:15.gif}}
 * As usually... <<BR>> {{attachment:16.gif}}
 * Done! <<BR>> {{attachment:17.gif}}

===== Install the bootloader (GRUB) =====
In Jessie (8.0), and I believe Wheezy (7.0), the installer will install [[Grub|GRUB]] even on RAID installs. However, GRUB can not install to a RAID device (e.g., `/dev/md0`), but will nonetheless work fine.
 * When asked to install bootloader, install to first device: <<BR>>{{attachment:grub-install_sda.png}}
 * After first boot, consider executing `dpkg-reconfigure grub-pc` (or `dpkg-reconfigure grub-efi-amd64` on EFI systems), and install to all devices. This way, your system will still boot correctly even if you reorder your drives. <<BR>>{{attachment:grub-install_sda+sdb.png}}

===== Install the bootloader (lilo) =====
''At the end of the installation...''
 * In Lenny (5.0), DebianInstaller automatically switch to [[LILO|lilo]] when you have root on RAID: <<BR>>{{attachment:20.gif}}

===== Reboot Debian =====
 * Debian is booting: <<BR>> {{attachment:oo.gif}}


==== Using D-I rescue, to reinstall lilo ====
Thanks to DebianInstaller's rescue mode, it's very easy to recover a problem :

 * Simply boot on the CD, and choose ''rescue'' mode, then after the usual DI prompt, you get : <<BR>> {{attachment:rescue00.gif}}
 * Then: <<BR>> {{attachment:rescue01.gif}}
## * Yeah, ok : inline:rescue02.gif
 * Reinstall/ rescue/restore lilo : <<BR>> {{attachment:rescue03lilo.gif}}

== See also ==
 * Recover a !DegradedArray RAID array ~-<<BR>> [[http://lists.debian.org/debian-user/2008/10/msg01989.html]]-~
 * DebianInstaller
 * http://www.tldp.org/HOWTO/RAID-HOWTO/
 * http://www.tldp.org/HOWTO/LVM-HOWTO/

[[CategoryDebianinstaller]]

Lenny (5.0) and later support having the root and /boot partition on RAID volume. Actually, you can have root on RAID1+LVM partition.

This page contains some screenshots to demonstrate it, and applies to Debian 5.0 through, at least, 8.0.

Root on software RAID+LVM

In this example, we use virtual machine (qemu or kvm)... we can play, and break them ;-)

  • $ sudo apt-get install kvm
    
    $ qemu-img create -f qcow2 hda.qcow2 4G
    Formatting 'hda.qcow2', fmt=qcow2, size=4194304 kB
    
    $ qemu-img create -f qcow2 hdb.qcow2 4G
    Formatting 'hdb.qcow2', fmt=qcow2, size=4194304 kB
    
    $ kvm -hda hda.qcow2  -hdb hdb.qcow2  -cdrom debian-lenny-i386-netinst.iso -boot d

Of course, you need to download a cdrom image.

Root on RAID+LVM example

Those few screenshots show how to install root on lvm on raid :

Once you have reach DebianInstaller partitioning screen...

Choose manual partitioning, then on each disk, manually create a partition (same size on both disks).

Create partitions for RAID
  • Use as "Physical volume for Raid" :
    00.gif

Configure RAID
  • We have a raid partition on each disk:
    01.gif

  • Choose the type of multidisk device to be created:
    02.gif

  • We have two partition:
    03.gif

  • (In this example, we have no spare partition).
  • Let's select the partitions to use:
    04.gif

  • That's it !
    05.gif

Configure LVM
  • Let's configure the Logical volume manager:
    06.gif

  • First create a volume group:
    07.gif

  • Here, I chose the name vg1 for the group:
    08.gif

  • We have only one raid device:
    09.gif

  • Let's create the logical volume (kind pf partitions):
    10.gif

  • Our Logical volume (LV) will use some disk space from vg1 (which belongs to md0):
    11.gif

  • I named my partition foobar_root:
    12.gif

  • In this example, we wont split the filesystem (we won't even bother to create a swap, which is a bad idea), so I use all the disk space. (which again isn't a good idea, since it's so easy ro resize a partition with LVM)
    13.gif

  • Finish:
    14.gif

Use the LVM volumes
  • Let's assign and format the volumes (partitions):
    15.gif

  • As usually...
    16.gif

  • Done!
    17.gif

Install the bootloader (GRUB)

In Jessie (8.0), and I believe Wheezy (7.0), the installer will install GRUB even on RAID installs. However, GRUB can not install to a RAID device (e.g., /dev/md0), but will nonetheless work fine.

  • When asked to install bootloader, install to first device:
    grub-install_sda.png

  • After first boot, consider executing dpkg-reconfigure grub-pc (or dpkg-reconfigure grub-efi-amd64 on EFI systems), and install to all devices. This way, your system will still boot correctly even if you reorder your drives.
    grub-install_sda+sdb.png

Install the bootloader (lilo)

At the end of the installation...

Reboot Debian
  • Debian is booting:
    oo.gif

Using D-I rescue, to reinstall lilo

Thanks to DebianInstaller's rescue mode, it's very easy to recover a problem :

  • Simply boot on the CD, and choose rescue mode, then after the usual DI prompt, you get :
    rescue00.gif

  • Then:
    rescue01.gif

  • Reinstall/ rescue/restore lilo :
    rescue03lilo.gif

See also

?CategoryDebianinstaller