Grub

siawash · 12-10-2009, 08:37 PM

Hello, I recently installed Mandriva 64 bit 2010 on my new machine.I have two hard drives. The primary drive is storing windows 7. SDA, and Linux on SDB.

I always thought you put grub in the root when your using stand alone linux and in master boot record of sdb if you have a dual boot. But the install only worked when I put grub in master boot record of SDA where windows is stored. So my question is what happens if grub becomes corrupted.? Would I have to reinstalled windows?

Here is my menu list

Code:

[root@localhost boot]# cat /grup
cat: /grup: No such file or directory
[root@localhost boot]# cd /grub
bash: cd: /grub: No such file or directory
[root@localhost boot]# 
[root@localhost boot]# cd grub
[root@localhost grub]# ls
device.map      install.sh*       menu.lst.example   stage2
device.map.old  install.sh.old*   menu.lst.old       ufs2_stage1_5
e2fs_stage1_5   iso9660_stage1_5  minix_stage1_5     vstafs_stage1_5
fat_stage1_5    jfs_stage1_5      reiserfs_stage1_5  xfs_stage1_5
ffs_stage1_5    menu.lst          stage1
[root@localhost grub]# cat menu.lst
timeout 10
color black/cyan yellow/cyan
gfxmenu (hd1,4)/boot/gfxmenu
default 0

title linux
kernel (hd1,4)/boot/vmlinuz BOOT_IMAGE=linux root=UUID=c57aa7a1-3fa7-49ca-8478-d9762aaad10b resume=UUID=cbc0f4f2-fbd0-414d-90e1-cca612949c18 splash=silent vga=788
initrd (hd1,4)/boot/initrd.img

title linux-nonfb
kernel (hd1,4)/boot/vmlinuz BOOT_IMAGE=linux-nonfb root=UUID=c57aa7a1-3fa7-49ca-8478-d9762aaad10b resume=UUID=cbc0f4f2-fbd0-414d-90e1-cca612949c18
initrd (hd1,4)/boot/initrd.img

title failsafe
kernel (hd1,4)/boot/vmlinuz BOOT_IMAGE=failsafe root=UUID=c57aa7a1-3fa7-49ca-8478-d9762aaad10b failsafe
initrd (hd1,4)/boot/initrd.img

title windows
root (hd0,0)
makeactive
chainloader +1

title desktop 2.6.31.5-1mnb
kernel (hd1,4)/boot/vmlinuz-2.6.31.5-desktop-1mnb BOOT_IMAGE=desktop_2.6.31.5-1mnb root=UUID=c57aa7a1-3fa7-49ca-8478-d9762aaad10b resume=UUID=cbc0f4f2-fbd0-414d-90e1-cca612949c18 splash=silent vga=788
initrd (hd1,4)/boot/initrd-2.6.31.5-desktop-1mnb.img

title desktop 2.6.31.6-1mnb
kernel (hd1,4)/boot/vmlinuz-2.6.31.6-desktop-1mnb BOOT_IMAGE=desktop_2.6.31.6-1mnb root=UUID=c57aa7a1-3fa7-49ca-8478-d9762aaad10b resume=UUID=cbc0f4f2-fbd0-414d-90e1-cca612949c18 splash=silent vga=788
initrd (hd1,4)/boot/initrd-2.6.31.6-desktop-1mnb.img
[root@localhost grub]#

And what about triple booting?

bigrigdriver · 12-10-2009, 08:53 PM

No, you won't have to re-install windows. You will need a windows install disk so that you can run fixmbr to restore the windows mbr.

As for grub becoming corrupted, that would most likely happen if you go fiddling about with partitions, and the partition table in the mbr no longer reflects the actual partition scheme.

The safest procedure to follow when installing operating systems is to make a copy of your mbr before installing another OS. Then you have a backup that you can restore if things go badly.

As for triple booting, when you install the third OS, be careful to specify installing grub to the root partition of the new OS, and not to the mbr. When the installation is complete, open file /boot/grub/menu.lst (grub.conf on some distros) and copy the menu entry for the new OS. Then mount the partition of the first Linux you installed, and paste that menu entry into the menu.lst of that OS. When you reboot, the third OS should be listed.

These questions have been addressed many times in these boards. Use the search feature to find out more about them.

jhwilliams · 12-10-2009, 08:56 PM

I have always put grub in the mbr. I don't think a corrupt mbr is a particularly valid concern, but you can always back it up if you're worried.

I have had up to a 4-way boot using grub in the mbr -- for Linux, it's as easy as pie. For windows, no big deal either, just chainload the boot code on the windows partition. As for having to reinstall windows: no -- in fact, doing so will automatically cream grub in your mbr. But, if you've made that backup, and have the same partition layout, then you don't have to worry! :-)