HowTos/Root Filesystem on external media

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This can free up most of your memory for RAM rather than storing files. The 14 MB of internal flash is still used by a ROM. However, in the case of a SL-5500, you get 64 MB of RAM. Additionally, you can have multiple loop-images, and choose which one is booted on startup. For example, one might be opie-3.5.4, another gpe, and another the latest release candidate of hentges with cardfs.


WARNING: Do NOT move rootfs of your Collie with 2.4 kernel to a CF card! Suspend/resume does not work because the CF card cannot be unmounted. Further, suspending in that state really messes up the kernel. See Collie/TipsAndTricks for details.

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Rootfs on SD/CF

Warning: these instructions are unclear, especially on what kernel to use. They will leave you with a non booting system if you use the 3.5.4.2-rc2 zimage and initrd from hentges as instructed(?). 3.5.4 kernels do work.

These are the steps that worked for an SL-5600 for OpenZaurus version 3.5.4.2-rc2 where a 1 GB SD card was used as the root filesystem. They may or may not work for other configurations. Proceed at your own risk.

Here I assume we start with an initially working system. It is important that you have an extra SD or a CF card, where you put the installation files for the initial system before starting so that you can go back to that initial system if something goes wrong.

1. Partition the SD card:

My initial system did not have fdisk. So if you don't have an SD card reader, this means you will first have to do a standard installation (see Install, do the bootstrap for instance), setup a connection between your linux desktop and the zaurus (e.g. HowTos/USB_Networking).

Once you have a working linux system on zaurus, which has an fdisk. After umounting /mnt/card, type: 

fdisk /dev/mmcblk0

in general replace the device name (and mount point, when unmounting) with the relevant device name for your external medium.

  • Partition the disk as you like. I created a linux (83) (%90 of the drive) and a linux swap partitions (82) (%10 of the drive).
  • Make the filesystem 
mkfs.ext2 /dev/mmcblk0p1

You can use mkfs.ext3 as well, and "/dev/mmcblk0p1" in general conrresponds to the partition you want your OpenZaurus system installed. If you created a swap partition also do 

mkswap /dev/mmcblk0p2

now mount /dev/mmcblk0p1 /mnt/card so that you have access to it.

2 Download and extract the Tarballs

We want to get the rootfs tarballs (*-rootfs.tar.gz).

Currently you can do this by going to the OpenZaurus download site ([1]), select "all files seperated" link for your platform then go to the tarballs directory.

pick the tarball for the gui platform of your choice. Download and copy to /mnt/card.

3 Boot and cleanup

Now you can reboot your system. Bring the altboot menu. Choose "advanced" (5), Then choose "Install rootfs from tar.gz" (8). The installer will guide you on the rest.

Also, don't forget to remove unneccassary files after the installation, configure your /etc/fstab so that the SD/CF card is not mounted twice (and if you have a swap that needs to be turned on add that too). Note that when installing new software, you should NOT choose sd as the destination. In fact it may be wise to delete that destination from the /etc/ipkg.conf file altogeter if it exists.

Next time you should choose "boot from SD" (3) from the altboot menu. In my case, I had to restart the first time I tried to boot into Opie.

Alternative

Altboot also allows the use of an imagefile in a vfat formatted card. This has various adantages.

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Notes: 

Scenario:
I am getting two altboot menus when booting off SD or CF / altboot is looping,
(or the altboot menu seems to be looping into itself and crashing (: )

Solution:
The second altboot prompt is coming from the installation on your SD / CF card.
Do not open the second altboot prompt, and if you do, select [1] for Normal Boot.
Do not try to use any other options (booting into init=/bin/sh works tho)



This comes with new opz roms.  It can be installed on some other systems, allowing 
you to boot a filesystem from a source other than the rather limited 
internal flash memory.



This is a pack of apps for Opie that can be installed after a standard or 
tarball (altboot) hentges installation.
  • Note: You generally need to boot your loop image after installing it, before you can restart and install cardfs via its boot-up installer. Otherwise, you will end up with a big "new media detected" dialog upon boot that you cannot get past.
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