View Full Version : Primary Disk Failed Raid 1

31st May 2006, 01:12 PM
Hi all,

I had a software raid 1 installation, the primary hard disk failed this morning, when i took it out and tried to boot i get the error


I have a new hard disk to replace the primary (both are IDE Disks)

Any advice to how to get the machine to boot up again and rebuild the mirror on the primary.

31st May 2006, 01:42 PM
Just some more info

Currently i have the following setup

Primary Master IDE -- 40gb windows partition (replacement disk for failed disk)
Secondary Master IDE -- 40gb

If i boot into linux rescue mode i cannot mount any filesystem but can get to the command line.

31st May 2006, 01:58 PM
lol im a complete noob with this stuff

/dev/hda1 NTFS 39198

/dev/hdc1 Software Raid 102
/dev/hdc2 Software Raid 2024
/dev/hdc3 Software Raid 37080

Ive just listed the above from disk druid during installation - i didnt complete the install because i need it to boot off hdc1 (i cant lose the files on the system) I thought with raid 1 if one disk failed the other would be bootable.

I assume i have to create the partions on hda and then somehow rebuild the mirror and get grub to see the drive - im lost :)

1st June 2006, 02:19 PM
Ok i have now booted with a knoppix cd - and I can see the secondary drive with all my files ,,,, so the mirror is there but i cant edit any of the files or boot off the drive ------ i cant even copy my website or mysql files to my memory stick through knoppix - if there is anyone out there who could help with this ,,, i need to get this running again by tomorrow - and really dont want to reinstall everything

2nd June 2006, 07:59 AM
to get your machine booting you need to set up GRUB on the secondary (working drive).
This can be done from the rescue system.

I can't give you more specific advise without knowing some more about your system. Where the two drives SATA or IDE? If IDE where they on separate channels or master/slave on the same channel?

3rd June 2006, 12:59 AM
thanks for the reply,

They are two ide drives, one on primary master the other on secondary master,

I tried booting in rescue mode ,,, but i could not mount the file system.

3rd June 2006, 01:03 AM
I have managed to reinstall the server with two new disks,,,,, and have managed to get my files off of working drive. I would still love to know how to install grub on the working drive in case of future upsets and if possible is there a way to get the mirrored drive to boot regardless of which drive fails?


3rd June 2006, 08:57 AM
if you can get to the command-line in the rescue system you need to mount the root filesytem on the second disk


mkdir -p /mnt/tmp
mount -t ext3 /dev/hdb2 /mnt/tmp

assuming root is on the second partition

then run grub from the mounted partition


#tell grub you want to work on the secondary disk
device (hd0) /dev/hdb

#tell it that /boot is on the second partition
root (hd0,1)

#install the bootloader into the MBR of /dev/sdb
setup (hd0)

obviously you might have to change those commands depending on what partition /root and /boot live on
hope that helps

5th June 2006, 11:10 PM
Ill give that a shot ,,, thank you for the replies- much appreciated ,