Booting from a flash card

This article covers the steps you need to follow to boot from a flash card with an N800 on N810. The process is somewhat involved, so some familiarity with the command line is recommended.

Advanced users may wish to read advanced booting as well, for more advanced booting-related configuration and setup information.


[edit] Why would we want to boot from a flash card?

  • For more space to install applications.
  • An easy-to-use bootable backup.
  • To improve performance (note, this is dependent on the quality of your flash card).

[edit] Gain root access

First of all you need to be able to gain root access.

[edit] Partition your card

Follow the instructions to partition your card.

[edit] Install the necessary tools

First, we need to install wget, so open Xterm and, as root, run:

apt-get install wget

Then run:

mkdir -p /home/user/bin
cd /home/user/bin
chmod +x tar

Then, to install the proper filesystem tools, temporarily add Extras-devel and run:

apt-get install e2fsprogs

NOTE: Do not upgrade existing packages with Extras-devel enabled as this may break things in new and interesting ways.

Remove Extras-devel when finished.

[edit] Install bootmenu

Now we need to download and install fanoush's initfs flasher, so, as root, run:
Note, although putting initfs_flasher in the directory given is not required, it cannot be placed on a FAT partition (i.e., one of the cards).

cd /home/user/bin
tar zxvf initfs_flasher.tgz
cd /home/user/bin/initfs_flasher/

[edit] Configuration

This is an optional step, but if you want to customize the bootmenu to properly reflect your partitioning setup, change the partition labels, and a number of other options, then you'll need to rename the appropriate bootmenu.conf.device.example file to bootmenu.conf and edit it to your liking. The README included with flasher and the comments in the configuration file should be enough to tell you what everything is.

The flasher will ask you if you want to include your bootmenu.conf file if you renamed it properly.

[edit] Flash the initfs

cd /home/user/bin/initfs_flasher/

Follow the onscreen instructions. You can answer yes to all of these questions if you don't understand what they mean.

[edit] Set the default boot device

Once the initfs is flashed, you may wish to change to default boot device so the tablet will boot into your preferred partition without intervention. To do this, as root, run:

chroot /mnt/initfs cal-tool --set-root-device ask:mmc2

To set the default to partition 2 on the internal card. If you would like to set the default to something else, the device is mmc# (where # is the partition number) for the internal card, and mmc1# for the external card. To set it back the default behavior of booting from the built-in flash, use flash.

On the N810 with latest Diablo version (5.2008.43-7), the device name is slightly different: immc# for the internal card and mmc# for the external one. For details see inside bootmenu.conf (or The name is customizable and corresponds to the MENU_x_ID="name" line of the item x you want to select.

[edit] Clone to the card

Many thanks to milhouse for writing and maintaining this script.

Now it's time to clone your install over to partition 2 of the internal card. The script works in stages to allow better control and error detection, and should take about 10 minutes to complete:

  • 0 - Create ext2 filesystem on partition 2 of the Internal memory card
  • 1 - Mount partition 2 as /opt
  • 2 - Mount rootfs as /floppy
  • 3 - Perform cloning process
  • 4 - Commit filesystem updates and unmount /floppy and /opt

So, as root, run:

cd /home/user/bin
./ 0

If the following error occurs: "Unable to locate mbcache.ko - aborting" follow the instructions per this link: [1]

./ 1

If the following error occurs:
"Installing ext2.ko module and mounting Internal Flash card, second partition... insmod: can't open '/mnt/initfs/lib/modules/current/ext2.ko': No such file or directory mount: mounting /dev/mmcblk0p2 on /opt failed"
do the following (similar to the above remedy during error of "./ 0")
cp /mnt/initfs/lib/modules/$(uname -r)/ext2.ko /lib/modules/$(uname -r)/
and repeat "./ 1"

./ 2
./ 3
./ 4

Your device will reboot when done, and you can select the partition you want to boot from from the bootmenu.

[edit] Remove the menu

If you decide you do not wish to see the bootmenu any longer, you can uninstall it by either reflashing the whole OS image, or just flashing the initfs (in Linux and OS X) by running:

sudo ./flasher-3.0 -F <FIASCO image> --flash-only=initfs -R

[edit] Advanced booting

For more advanced configuration and setup information for booting-related stuff, please see advanced booting.