Linux on Hard Drive Partition, Bootloader on USB Flash Drive

arch linuxboot-loadergrub2usb-drive

How can I use a USB flash drive to boot Linux from a partition on (another) hard drive?

I'm trying to install Linux on an encrypted partition on the hard drive (using LVM on LUKS).

Since /boot must be on a separate, unencrypted partition, I would like to store it on a USB flash drive.

My plan was to install GRUB (2) to the flash drive (/dev/sdb) and boot Linux from it's MBR, or if the drive was unplugged simply boot Windows from the hard drive's (/dev/sda) MBR.

I installed GRUB (2) to /dev/sdb, but when I tried to boot from the flash drive I got the following message:

Grub Loading

After a couple of seconds I got an additional message:

Read Error

For testing purposes, I tried to delete the contents of /boot, and I got the same message after booting again from the flash drive.

PARTITIONING DETAILS

/dev/sda (Hard Drive):

MBR: Windows Bootloader
/dev/sda1 - Windows System Partition
/dev/sda2 - Windows Boot Partition
/dev/sda3 - Windows Data Partition
/dev/sda4 - Linux partition

/dev/sdb (USB Flash Drive):

MBR: GRUB
/dev/sdb1 - Linux /boot Partition

GRUB DETAILS

/etc/default/grub:

GRUB_CMDLINE_LINUX="cryptdevice=/dev/disk/by-uuid/$SDA4_UUID:vg root=/dev/mapper/vg-root resume=/dev/mapper/vg-swap cryptkey=/dev/disk/by-uuid/$SDB1_UUID:ext2:/key"
..
GRUB_DISABLE_LINUX_UUID=true

Installation command

grub-install --target=i386-pc --recheck /dev/sdb

I'm using Arch Linux.

Best Answer

Have you tried

grub-install --target=i386-pc --recheck /dev/sdb1

Note the /dev/sdb1 which appears to be your USB device.

MBR: GRUB
/dev/sdb1 - Linux /boot Partition

Maybe try this :

title Start Ubuntu from USB DISK (PC)
root (cd)
kernel /boot/vmlinuz file=/cdrom/preseed/ubuntu.seed boot=casper noprompt cdrom-detect/try-usb=true persistent
initrd /boot/initrd.lz
boot

Related Solutions

USB – Installing Grub 2 on a USB Flash Drive

You got me curious how this would be done. The Pendrivelinux site had a tutorial I did this from my Mint 9 install instead of a live cd as the site suggests.

I started with finding the location of my USB drive in a terminal I ran df it returned the location of the device as

/dev/sdg1   /media/LINUXUSB

after that I ran

sudo su

and then to install grub 2

grub-install --no-floppy --force --root-directory=/media/LINUXUSB /dev/sdg1

I had to use --force additionally, the example on the site did not. Then I did

cd /media/LINUXUSB/boot/grub

The site gave a link to download a copy of grub.cfg to the /boot/grub directory on my USB drive. The link was

wget http://pendrivelinux.com/downloads/grub.cfg

After that I edited grub.cfg to reflect the iso's on my USB drive.

set timeout=10 set default=0

menuentry "Run Fedora" {
    loopback loop /Fedora13.iso
    linux (loop)/isolinux/vmlinuz0 boot=isolinux iso-scan/filename=/Fedora13.iso splash --
    initrd (loop)/isolinux/initrd0.img
}

menuentry "Run Ubuntu" {
    loopback loop /ubuntu-10.04-netbook-i386.iso 
    linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/ubuntu-10.04-netbook-i386.iso splash --
    initrd (loop)/casper/initrd.lz
}

menuentry "Run Clonezilla" {
    loopback loop /clonezilla.iso
    linux (loop)/live/vmlinuz boot=live iso-scan/filename=/clonezilla.iso splash --
    initrd (loop)/live/initrd.img }

I found that in the different iso's, vmlinuz and initrd were located in a different directory. I was able to get all three to start the boot process; but, only Ubuntu to actually load. If I figure out what I need to get the other two to finish loading, I will add that later. I have not tried any other iso's just these three.

Related Question