EXTERNAL HARD DISK INSTALL HELP

Hi, my name is Albert and i'm having a trouble installing the OS to an external hard disk.
All the installation is ok, and i can boot on the computer on which i have made the installation. But when i try to boot on a different computer, it says grub rescue error and i can't boot. The grub works only in the computer that i used to install it to an external hdd, not on any other computer

Any help about how to fix it would be very appreciated
sorry for my bad English, i'm from spain

Thanks

Hi Albert,

you loaded the Bootloader not onto the external drive but onto the HDD of the other PC, when you move the external drive to another PC, it cannot find the bootloader because you didn't write it to the external drive!.

When you installed, it asked you where the bootloader should be loaded (installed), you most likely choose "/dev/sda" which is the internal HDD, you should have selected /dev/sdb or "d" which is the external drive.

See:

https://help.ubuntu.com/community/Grub2/Installing

https://help.ubuntu.com/community/Boot-Repair

Hope it helps.

thanks, i will try it. But i have one question (sorry, i am 100% newbie on linux). Boot repair disk will repair the grub on the external hdd only? can you choose in which disk do you want to run it? thanks

I know you are new to Linux but there are certain things you cannot get around, see this link:

http://ubuntuguide.net/how-to-restore-g ... hard-drive

what would be the easy route for you is to re-install and keep your eye on the question about where the bootloader should be placed, select the "Something Else Method" :

viewtopic.php?f=6&t=4848

See pic 1:



On pic 2, you will see "Device for bootloader installation", that is where you must choose the external drive by clicking on the arrow on the right of the bar that states "/dev/sda" and change it to "/dev/sdb":



Hope it helps.

So, i select "something else" , put the bootloader onto /deb/sdb and select install now? But i only have a sda1 partition

The device is sdb, and i only have a sdb1 partition. Can i install the OS on that sdb1 partition? is ext4 formatted

Hi Albert,

if you are only using the external drive, then put the bootloader on that (/dev/sdb), if you want to install permanently to a HDD, then select /dev/sda!.

If you install the bootloader to /dev/sdb on the external drive, you can take it with you and boot from it!.

The following is for 13.10 but its the same story:

http://www.linuxbsdos.com/2013/10/23/ho ... ard-drive/

Hi, Wolfman
I have done it as you said, following the link and everything. The installation works well... on the computer used to create it. Is a LaCie P9220 hard disk, i used 4 Gb to the Swap partition and the remaining 927 Gb to the ext4 partition

Now the grub error is: Invalid Extent (on a different computer). Any idea of how to solve it? Thanks

Hi Albert,

how big is your "root" partition on your external drive?, according to this link, anything (more or less) above 25GB's (I use about 20GB's myself!) will cause that message!:

http://ubuntuforums.org/showthread.php?t=1997316

Just to point out, I recommend 3 partitions, 1 swap, 1 root (Ca 20GB'S) and the rest for your home partition, see the partitioning guide for more info:

viewtopic.php?f=6&t=2601

So, I create a 4 gb swap partition, a 20 gb root partition and a (aprox 900 gb) home partition ( home is the partition i choose to install on it?) and select the bootlosder on /deb/sdb?

You've got it Albert, all 3 partitions including the bootloader on the external drive!.

Select /dev/sdb for the bootloader!.