Hello,
I was wondering could multiple distributions be possible on the same partition (assuming there is disk space). So for a grub.conf below are there any precautions I should take while installation? How safe is it because I wouldn't want my existing(FC2) working partition blowing off? Please advice....

-----------
title Fedora Core (2.6.5-1.358)
root (hd0,7)
kernel /boot/vmlinuz-2.6.5-1.358 ro root=LABEL=/ rhgb quiet
initrd /boot/initrd-2.6.5-1.358.img
title Damn Small Linux (0.9.3)(2.4)
root (hd0,7)/dsl
kernel /boot/dsllinuz-2.4 ro root=/dev/hda8/dsl rhgb quiet
initrd /boot/initrd-2.4.img
title Redhat9 (2.4.56)
root (hd0,7)/rh9
kernel /boot/vmlinuz-2.4.56 ro root=/dev/hda8/rh9 rhgb quiet
initrd /boot/initrd-2.4.56.img
-----------

Above(for Redhat9) could I replace the
kernel /boot/vmlinuz-2.4.56 ro root=/dev/hda8/rh9 rhgb quiet
with
kernel /boot/vmlinuz-2.4.56 ro root=LABEL=/ rhgb quiet
since the previous line
root (hd0,7)/rh9
has set the root?

Thank you,
regards,
Prasad

Do you mean on the same hard drive?

Multiple distributions sharing the same root partition is a nightmare waiting to happen. It is far too likely one distribution will overwrite the configuration/libraries used by the other and it very well could end up with both having major package dependancy problems.

To answer reddazz: Yes on the same harddisk

and

jtshaw: correct me if I am wrong but if I declare the root as (hd0,7)/rh9 won't everything be referenced from(relative to) (hd0,7)/rh9 (which is also /dev/hda8/rh9) for say Redhat9 per the grub.conf posted earlier.

Lets refer to the root(set as (hd0,7)) from the grub file as 'root'. And the root for a distribution as root.
Even when a reference to /dev/hda8 is made, it is after the 'root' has been set so I am thinking if Redhat9 were installed in the rh9 directory of the FC2 partition, /dev/hda8 for Redhat9 would actually be (hd0,7)/rh9/dev/hda8 and /dev/hda8 for FC2 would be (hd0,7)/dev/hda8. Is this correct?

Thank you,
regards,
Prasad

You can certainly install multiple distributions on the same hard drive. I've had setups with several test distributions that even shared /home partitions before. I don't see a reason why they couldn't also share the same /boot partition.

But he asked about the same partition. Which I took to mean they would both use the same root partition, which is VERY dangerous and certainly not something I would recommend.

Directories are in fact based on a defined root. So if I have a setup like this

hda1 = /boot
hda2 = swap
hda3 = / (for OS1)
hda5 = / (for OS2)
hda6 = /home

Then I see no reason why OS1 (which would of course have root=/dev/hda3 passed into it's kernel at boot) couldn't mount hda1 as /boot and hda6 as /home while OS2 (which would have /dev/hda5 passed into it's kernel on boot) could also mount hda1 as /boot and hda6 as /home.

However, I wouldn't recommend having any kind of setup where /etc, /var, /usr, or /opt were shared between two different distributions unless you really know what you are doing and are very careful not to blow up dependancies for one distribution by installing packages from the other.

Yep, thats what I was trying to clarify. You can as mentioned install multiple os's on one hard disk. If installing multiple Linux distros they can share the same /home but not the same / root partition coz they will just make the system unusable or unstable if it works at all coz they mess up the config files from different distros.

Well, I certainly wouldn't use the same drive/partition/directory as root for all distributions. I was thinking:

(hd0,7)/ = / (for OS1, FC2)
(hd0,7)/rh9 = / (for OS2, Redhat9)
(hd0,7)/dsl = / (for OS3, Damn small linux)
(hd0,7)/xxx = / (for OS4, your favourite linux).

I am sorry I didn't post the question more clearly.

Thank you,
regards,
Prasad