Setting a multiboot environment

[ArisVer]

I want to make a multiboot disk with some distributions (six?). I have made a 2GB /boot partition for the lot.
The first distribution I installed was Ubuntu lucid with debootstrap. I made a /(swap) and /(root) partitions for lucid. Only the /(root) partition was mounted for the bootstrap process and /mnt/maxubrt is the mounted location.
The following boot files have been installed.

Aris@Aris2:/mnt/maxubrt$ ls /boot
config-2.6.32-5-686 grub initrd.img-2.6.32-5-686 lost+found System.map-2.6.32-5-686 vmlinuz-2.6.32-5-686

I can move the files to the /boot partition I created but now I have the following questions. Is it better to have a separate /boot partition for all? Will some of the files be overwritten by the other distributions (installations) if they are identical?

To make things clear,

Aris@Aris2:/mnt/maxubrt$ blkid
/dev/sda1: LABEL="MaxBoot" UUID="e7fd7902-7ab0-4ca1-8cbf-3c43ebf1d0ff" TYPE="ext4"
/dev/sda2: LABEL="MaxUbSwp" UUID="82e96ef7-c7d6-4ce9-9e0c-f069e84642fa" TYPE="swap"
/dev/sda3: LABEL="MaxUbRt" UUID="aed7b4d4-4eae-407b-ab43-bf359d9bda8f" TYPE="ext4"
Aris@Aris2:/mnt/maxubrt$ mount
/dev/sda3 on /mnt/maxubrt type ext4 (rw)

 

[Nothinman]

Why are you going through the hassle of trying to load them all natively instead of just picking one as the host and loading the reset in a VM?

 

[ArisVer]

This is my old computer and only has 1GB ram which is the maximum. If I am correct it will be difficult to setup a VM with just 1GB ram. I only turn it on once in a while now and have a 30GB disk as a backup system there. I want to put the systems there just for a look and see their differences as I have only been using Gnome for almost a year now. The other disk is a spare one (250GB) and I will not install KDE there. It also gives me something to do like learning to setup a multiboot environment and in the process learn a bit how grub behaves. I am not familiar enough with VMs, I am going to try it with a KDE on this computer when I get some ram. Btw, I just remembered that I have tried once or twice to start a VM unsuccessfully on that computer, my error was something to do with disk space IIRC.

 

[lxskllr]

I've never multi-booted GNU/Linux on the same physical drive, but if I were to do it, I'd try to keep everything separate except for swap. If you're just doing this to try different DEs, it's easier to install the DEs, and play around. You can pick which one you want to use at login, and easily switch between them, or uninstall them.

It looks like you run Debian as your main O/S? I'd install Ubuntu so you can checkout Unity, and then install the different DEs to your Ubuntu install. Once you're finished thrashing that install, put something completely different in; maybe fedora. That'll give you a idea of how other distros work. Anything based on Debian(Ubuntu or any of the hundreds of offshoots) will be very similar to vanilla Debian. You could really check them out by running a LiveCD to see what the fit/finish is like. Day to day use will pretty much be Debian.

 

[ArisVer]

Thanks for your advice. I will make the same partitions for all versions of DE for the same distributions which will be all debian based for the simplicity of working with the same tools and not having to figure out the rpm packages. How do I configure the /boot partition for the lot? I guess I will have to install Grub on its own there and configure it. I use Debian as my main OS (and only OS) in my main computer.

Edit. I do not want to try non-debian based distributions right now, because of the packages and their installation process, and because of the commands which might be different. I will do that sometime, but it will be after a few years.

 

[mv2devnull]

DE (Desktop Environment) is just an application that is started by DM (Display Manager) -- an another application. One distro (OS install) can have multiple DM (gdm, kdm, xdm) installed although only one is in use. User selects DE when login in, so obviously multiple DE can be simultaneously installed.

If two distro's are simultaneously installed, use shared /boot, and have files with same name, those files overwrite. That is not good even when the files are identical.

/boot does not have to be on separate filesystem. It can be on /. It is good to have /boot of one OS on separate filesystem though. BIOS should load that GRUB. That GRUB could start other OS by directly loading kernel from their filesystem, or by chainloading the GRUB of the other OS.

In either case the /boot of the other OS must be on a filesystem that GRUB can read. Legacy grub has limitations, but doesn't Debian family use grub2?

 

[lxskllr]

Legacy grub has limitations, but doesn't Debian family use grub2?

I'm not sure about stable, but the other Debians are on Grub2, as are all the popular derivatives I'm familiar with.

If sticking with a Debian base, I don't see much point in installing more than Ubuntu, and Mint. They both have desktop environments particular to their distros, but otherwise work the same as Debian. Everything else can be done by changing DEs.

 

[ArisVer]

Current Debian Squeeze 6.0.4 (stable) Grub version is

# grub-install -v
grub-install (GRUB) 1.98+20100804-14+squeeze1

I am using a separate /boot partition for my usual setup (on my main computer), but having a separate /boot partition for a few OSs is a different story. My initial thoughts was installing the boot files of all OSs there, but I was wondering about overwrites. It will be more simple to just install a standalone grub there (it is possible, right?, on it's own partition), to point to each OS having it's own /boot directory. Again, thank you for your advice on the DEs as I am not used to having more than one. I have one question here though. Why is it not possible to start two DE and have each of them on the Workstations place? I know I can do that through ssh but that means activating a second computer. From what you are saying, one has to log out and then start another session with the other DE.

 

[mv2devnull]

You can do user switching on some DM. Another user can log in and have a session. No idea whether (re)selection of DE is possible. Thing is, a DE session involves input, output, virtual files systems, etc. For example, plug in USB stick and ask yourself who should be the mapped owner of the files.

I think that those switched (simultaneous) sessions do use separate X screens. Or servers. I have not paid attention. In principle it should be possible to have N sets of display-mouse-keyboard and separate, simultaneously active session in each.

 

[ArisVer]

Ubuntu, gnome and xfce, and maybe lxde. Mint, the same. And Debian xfce. These are the first ones, possibly using ubuntu from time to time. I am thinking about LFS but I better do my reading first, so that means after this year. And installing Debian with blackbox, fluxbox or similar.

In Debian Gnome under System, Log Out User, there is a switch user button, but I did not use it since I am the only user here.
I have read that it is possible to activate more than one X session on the same computer, I have not tried that yet, http://www.hermann-uwe.de/tips-and-tricks/multiple-x11-sessions.

 

[Nothinman]

You can do user switching on some DM. Another user can log in and have a session. No idea whether (re)selection of DE is possible. Thing is, a DE session involves input, output, virtual files systems, etc. For example, plug in USB stick and ask yourself who should be the mapped owner of the files.

I think that those switched (simultaneous) sessions do use separate X screens. Or servers. I have not paid attention. In principle it should be possible to have N sets of display-mouse-keyboard and separate, simultaneously active session in each.

I think you're reading way too much into it. Sure, running separate X sessions with different DEs at the same time as the same user would be problematic. But most DMs now let you choose which DE you want on login so you can switch between them without issue and figure out which you like best.

Most USB sticks use FAT so the owner will be whichever user is logged into the console. No, I have no idea which would be the owner if you had multiple users logged into the same PC on multiple consoles. It would probably be a race which would end up in failure and weirdness, but disabling that auto-mounting stuff isn't that hard.