Changes between Version 10 and Version 11 of DiscosRaid

Timestamp:

Apr 10, 2012, 1:38:12 PM (12 years ago)

Author:

fernandofolino@…

Comment:

--

DiscosRaid

@@ -136 +136 @@
 
 http://piiis.blogspot.com/2009/03/change-slot-number-of-raid-1-device-by.html
+
+== Degraded Boot ==
+
+Si se rompe un disco "primario" del array, y el "secundario" no tiene instalado GRUB2, seguir las instrucciones de https://help.ubuntu.com/community/Grub2#ChRoot
+
+{{{
+ChRoot
+
+This method of installation uses the chroot command to gain access to the broken system's files. Once the chroot command is issued, the LiveCD treats the broken system's / as its own. Commands run in a chroot environment will affect the broken systems filesystems and not those of the LiveCD.
+
+   1. Boot to the LiveCD Desktop. The CD should be the same release and architecture (32/64 bit).
+   2.
+
+      Open a terminal - Applications, Accessories, Terminal.
+   3.
+
+      Only If the normal system partition(s) are on a software RAID (otherwise skip this step): make sure the mdadm tools are installed in the Live CD environment (e.g. by executing sudo apt-get install mdadm). Then assemble the arrays:
+
+      sudo mdadm --assemble --scan
+
+   4. Determine your normal system partition (the switch is a lowercase "L"):
+
+      sudo fdisk -l
+
+      If you aren't sure, run df -Th. Look for the correct disk size and ext3 or ext4 format.
+   5. Mount your normal system partition:
+          * Substitute the correct partition: sda1, sdb5, etc. 
+
+      sudo mount /dev/sdXX /mnt
+
+          *
+
+            Example 1: sudo mount /dev/sda1 /mnt
+          *
+
+            Example 2: sudo mount /dev/md1 /mnt 
+   6.
+
+      Only if you have a separate boot partition (where sdYY is the /boot partition designation):
+
+      sudo mount /dev/sdYY /mnt/boot
+
+          *
+
+            Example 1: sudo mount /dev/sdb6 /mnt/boot
+          *
+
+            Example 2: sudo mount /dev/md0 /mnt/boot 
+   7. Mount the critical virtual filesystems. Run the following as a single command:
+
+      for i in /dev /dev/pts /proc /sys; do sudo mount -B $i /mnt$i; done
+
+   8. Chroot into your normal system device:
+
+      sudo chroot /mnt
+
+   9.
+
+      Only if (some) of the system partitions are on a software RAID (otherwise skip this step): make sure the output of mdadm --examine --scan agrees with the array definitions in /etc/mdadm/mdadm.conf.
+  10.
+
+      If the file /boot/grub/grub.cfg does not exist or it is not correct, (re)create it using
+
+      update-grub
+
+  11.
+
+      Reinstall GRUB 2 (substitute the correct device with sda, sdb, etc. Do not specify a partition number):
+
+      grub-install /dev/sdX
+
+      If the system partitions are on a software RAID install GRUB 2 on all disks in the RAID. Example (software RAID using /dev/sda and /dev/sdb):
+
+      grub-install /dev/sda
+      grub-install /dev/sdb
+
+  12.
+
+      Verify the install (use the correct device, for example sda. Do not specify a partition):
+
+      grub-install --recheck /dev/sdX
+
+      For a system on a software RAID, repeat this for all devices in the RAID.
+  13.
+
+      Exit chroot: CTRL-D on keyboard
+  14. Unmount virtual filesystems. Run the following as a single command:
+
+      for i in /sys /proc /dev/pts /dev; do sudo umount /mnt$i; done
+
+  15. If you mounted a separate /boot partition:
+          *
+
+            sudo umount /mnt/boot
+
+  16. Unmount last device:
+
+      sudo umount /mnt
+
+  17. Reboot.
+
+      sudo reboot
+}}}