I usually use in my Desktop at home Debian Etch (Stable), but as I also like Mandriva since I tested it, I wanted to install a dual boot system, with both Mandriva and Debian Etch, but I also wanted to have access to both file systems with the same permissions and even have the same /home partition for the two operating systems, so for this I needed to be sure to have the same user with the same UID and GUID in both systems.

To install this you will need Debian Installer and Mandriva Live CD, you can use this guide for any other combination of Linux, the real important things are:

• Be sure to have the first Linux installing grub on the MBR
• The second installed Linux should install grub on its root partition
• Use the UID and GUID for the users on both Linux distros

You can also have a Dual boot PC with the same Distro, just to have one for experimenting and the second for your stable work.

I first installed Debian as explained in this manual to install Debian Etch, be sure to left space for Mandriva, so you will need to select manual partition on this screen

And from that point continue like this:

Select manual configuration, so you can decide how your disk is going to be partitioned.

Select the disk, you wish to use (In my case I have only one)

Create a new empty partition on the disk

Now select the empty partition just created

And create a new partition on it

I will create first the swap partition, which will be used by the two operating systems, this could not be a good idea if you plan to suspend to swap (if you are using a laptop) in that case create one swap per operating system.

This will be primary partition

I chose to put it at the beginning

And select it to be a swap type partition.

Accept changes

Select once again the free space

And create another partition

This time I chose 8 Gbytes for the /home directory

And once again at the beginning

And the mount point is /home

Accept changes

Select once again the free space to create a new partition

And create it

This time I will use this as the Debian / (root) partition

At the beginning

Mount point "/"

And Finally finish with this, see that there is an unassigned space, which I will later use for Mandriva

Write changes to the disk, and then boot from your Mandriva disk, as this is a live CD you will have to boot it, and then choose to install it, here is how to install it on this machine.

Click on "Live Install"

This window will appear on your screen, just click on "next"

Select custom partition, this is the important step :)

Select the unformated room of the disk, and assign it to "/" (root), and the swap, as the swap for this system also. (remember that if you are using a laptop it could be better to create another swap for this system.

Should look like this

Format only the root partition, as on the /home you may have already data, and it was formated by the first system installed in this case (Debian)

Select to install Debian on the root partition

Just click on finish

On finish again :), and reboot your PC, you will have to enter on your first system, and edit grub menu, in my case I entered Debian, and added this lines to my /boot/grub/menu.lst file

title Mandriva
root (hd0,5)
chainloader +1

where hd0 is my first disk (the only one in my case) and the 5 following it, is the partition as it starts from 0, 5 is the sixth partition, so this means that grub should look for another grub on partition /dev/sda6, where I have installed the Mandriva grub.

Check your /etc/password and take note of your UID and also from the /etc/group take note of the GUID for the users you will create on both systems.

UID and GUID means (User ID, and Group ID) and are the third column of the files mentioned above.

Once you have done this, reboot your system again and this time boot from the second operating system, for the first time you will have to end the configuration so you will find a screen like this (if you are installing Mandriva as the second operating system)

Configure your ethernet

I chose DHCP

Select the parameters you prefer

Select to start connection at boot

You are done with network

choose a good root password

Create your new user, this part is important, be sure you assign the same UID and GUID that this user have on your first installed operating system, otherwise you will have permission issues.

Now you are done this is how my Mandriva looks like, check that I have created a file called, my_test_file.txt

On this screen at Debian you can see the same file created with Mandriva, actually the desktop looks the same, except for the wallpaper.