Linux Gurus - A question about booting from external drive

[ches111]

I have a Dell Latitude D600 with a meager 40gb hardrive.

I currently dual boot Centos (Enterprise edition of Linux) and Windows XP.

The 40gb is filled to the brim and I have no room for anything else.

So here is what I would like to do.

Move Internal drive to full Win XP pro (full 40gb)
Partition 80gb external to 2 ~40gb partitions (easy)
Install Linux (not Centos this time) on one of the external 40gb partitions.
Have grub loaded on the internal drive and point to the external to pickup the linux release.

save the second 40gb partition as Fat32 so both installs can mount/see it.

I know it is possible to load linux from an external just not sure if you can do it using grub/lilo off of the internal.

Any help would be appreciated.

They are doing a corporate XP pro base install in the AM on the 40gb internal drive. Do I need to reserve ANY space on the internal for grub/lilo? Maybe give them 38gb for WinXP?

 

[ches111]

Finally found my own answer..

Here it is :

http://en.opensuse.org/Installing_SuSE_on_External_USB_Drive

Looks like it is a matter of tricking grub to use hd0 and hd1 either way.

 

[bmouring]

The solution posted on the SuSE page may work fine for some situations but not all as GRUB will assign different hd numbers depending on multiple factors (your hardware, your kernel, your version of GRUB, etc.)

A safer (and IMHO more edifying) solution is to boot into a GRUB CLI and prod around the disks to find which hd number points to the external disk. An example of how to do this:


[*:00bb826638]Do your installation and then stop GRUB from booting automatically and drop into the GRUB CLI from there.
[*:00bb826638]When at the GRUB CLI ("grub>"), use GRUB's built-in tab-completion ability to investigate the system, for example type "geometry (hd[tab]" for a list of available disks and partitions along with detected filesystem types. Look for something like an EXT2 or EXT3 or a Reiser filesystem on a 0x83-type partition, this is a likely candidate for the partition you want.
[*:00bb826638]To investigate further, pick one of the likely candidate partitions (say, (hd1,0)) and again use tab-completion to investigate the contents of the partition, for example "geometry (hd1,0)/[tab]" reveals a few files and folders with names such as "grub/", "initrd-SOME_VERSION", "vmlinuz-SOME_VERSION", etc. This is very likely the boot partition that you are looking for.
[*:00bb826638]Edit the menu.lst/grub.conf to match your findings when in the CLI
You may also mirror this technique with a LiveCD or a straight-up GRUB boot cd to "feel out" a system.

Glad you found a solution, just wanted to add a little of my own experiences to the mix.

 

[dunklegend]

You don't need to format your other partition as FAT32.
I'm using Ubuntu and I installed an application called NTFS3G (I think) and that would let me mount and even write on the windows NTFS partitions.

 

[linux_0]

Yes NTFS-3G works great :-D

http://www.ntfs-3g.org/

You don't need to format your other partition as FAT32.
I'm using Ubuntu and I installed an application called NTFS3G (I think) and that would let me mount and even write on the windows NTFS partitions.