Share your knowledge at the LQ Wiki.
Go Back > Forums > Linux Forums > Linux - Software
User Name
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.


  Search this Thread
Old 10-24-2005, 01:06 AM   #1
Registered: Dec 2004
Posts: 145

Rep: Reputation: 15
How to boot from the 3rd disk while RAID1?

I just want to do this: Now there is 4 hard disks, to build RAID1 on RAID0.

I splite the partitions of every disk to 2 part: the system part and data part. data part will be build RAID1 on RAID0, and system part, to make the system always availabe, I build only RAID1 for disk partitions: /(sda1,sdb1,sdc1 & sdd1), /usr(sda2,sdb2,sdc2,sdd2).

Then I must setup grub on all these 4 disks to make the system can boot up from anyone when the previous disk is broken, so do this:
# grub
grub> install (hd0,0)/boot/grub/stage1 d (hd1) (hd0,0)/boot/grub/stage2 p (hd0,0)/boot/grub/grub.conf

grub> install (hd0,0)/boot/grub/stage1 d (hd2) (hd0,0)/boot/grub/stage2 p (hd0,0)/boot/grub/grub.conf
Now if I remove sda, the system can boot from sdb, GRUB works well. But then I go on remove sdb, I just get a command prompt of grub while boot:
If I run the right commands, I can boot the system:
grub> root (hd0,0)
grub> kernel /boot/vmlinuz-VERSTION ro root=/dev/md0
grub> initrd /boot/initrd-VERSTION.img
grub> boot
But I don't think it's convenience, what is the problem and what is the solution?

Old 11-07-2005, 07:56 AM   #2
Registered: Dec 2004
Posts: 145

Original Poster
Rep: Reputation: 15
I comment this 2 line, and it seems work:
# splashimage=(hd0,0)/boot/grub/splash.xpm.gz
# hiddenmenu

But now I have another problem. Using the previous way, if I remove sda and sdb, OK, I can boot up from sdc(set in BIOS) because it will been considered as (hd0) by stage1 on the MBR of sdc. But what about the condition when I re-insert 2 new disks. This 2 disks have nothing.

Will sdc stage1 takes new sda as (hd0)?

I tried in VMware, and I found in this case, sdc stage1 still take itself as (hd0), not the sda. But what about (hd1), (hd2) and (hd3)? I tried this to found:
grub> install (hd3,0)/boot/grub/stage1 d (hd2) (hd3,0)/boot/grub/stage2 p (hd3,0)/boot/grub/grub.conf
I found the behaviour of GRUB was not sure, sometimes it found the stage2 on sdb and sometimes on sdd.

What's wrong? Is it realy unsure? Or it is just the cause of the Virtual Machine?


Last edited by Chowroc; 11-07-2005 at 07:57 AM.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
add a new disk to raid1 array retrev Linux - General 1 04-08-2007 01:57 AM
FC3 Raid1 won't boot after new install mrbenconrad Linux - General 2 01-22-2006 03:19 PM
Installed GRUB on 3rd hard drive, how do I boot 1st drive? jesusphreak Linux - Newbie 4 04-06-2005 09:34 AM
Setting up a RAID1 config (Disk Mirroring) ajpalm Linux - Newbie 1 11-18-2002 03:42 AM
3rd install disk redhat 7.3 bw8 Linux - Newbie 2 10-06-2002 05:20 PM > Forums > Linux Forums > Linux - Software

All times are GMT -5. The time now is 07:14 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration