Testing/Reports/Sugar on a Stick Persistence

Presenting this method to a wider audience is still a work in progress. The working title is SoaS Loader. You will find a tutorial presentation of this method here http://soas-loader.readthedocs.org/. Limitations may be discussed on the talk page.

The starting point is

• a PC, laptop, or netbook
• a clean 2GB or 4GB USB stick to use as the target device.
• a Sugar LiveOS image to use as the "host" media.

It does not really matter what operating system you are using. To make your persistent Sugar on a Stick you will boot your computer with a Sugar LiveOS "host" media, which might be:

• A CD-ROM made from the Sugar.iso available from Sugar on a Stick/Downloads

The CD-ROM could be made from the default CD writing software of your PC.

• A UNetbootin USB as described in Sugar on a Stick/Installation Process
• A USB stick written with the Linux command dd from the Sugar.iso available from Sugar on a Stick/Downloads,

    sudo dd if=Fedora-Live-SoaSversion.iso of=/dev/sdX bs=8M

• A USB stick written with Nautilus (Files).
• or any other Sugar on a Stick.

Method

Boot your computer with the chosen LiveOS media. Once Sugar is running,

Either enter a console with Ctrl+Alt+F2,

or open the Terminal Activity, , from the Home list View.

Plug a clean 2GB memory stick, the target device, into the PC.

Run the command,

df -Th

to establish the device location.

extra detail.

First, running the command `df -Th` before plugging in the target stick, expect output like this:

[root@localhost ~]# df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
/dev/mapper/live-rw ext4      2.9G  2.1G  773M  74% /
devtmpfs            devtmpfs  2.0G     0  2.0G   0% /dev
tmpfs               tmpfs     2.0G   72K  2.0G   1% /dev/shm
tmpfs               tmpfs     2.0G  632K  2.0G   1% /run
tmpfs               tmpfs     2.0G     0  2.0G   0% /sys/fs/cgroup
/dev/sr0            iso9660   670M  670M     0 100% /run/initramfs/live
tmpfs               tmpfs     2.0G   32K  2.0G   1% /tmp
varcacheyum         tmpfs     2.0G     0  2.0G   0% /var/cache/yum
vartmp              tmpfs     2.0G     0  2.0G   0% /var/tmp

Then, running the command `df -Th` after the target stick is inserted, the command produces an extra line at the bottom:

[root@localhost ~]# df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
/dev/mapper/live-rw ext4      2.9G  2.1G  773M  74% /
devtmpfs            devtmpfs  2.0G     0  2.0G   0% /dev
tmpfs               tmpfs     2.0G   72K  2.0G   1% /dev/shm
tmpfs               tmpfs     2.0G  632K  2.0G   1% /run
tmpfs               tmpfs     2.0G     0  2.0G   0% /sys/fs/cgroup
/dev/sr0            iso9660   670M  670M     0 100% /run/initramfs/live
tmpfs               tmpfs     2.0G   32K  2.0G   1% /tmp
varcacheyum         tmpfs     2.0G     0  2.0G   0% /var/cache/yum
vartmp              tmpfs     2.0G     0  2.0G   0% /var/tmp
/dev/sdb1           vfat      1.8G  2.0K  1.8G   1% /run/media/liveuser/SanDisk

The new line reads:
/dev/sdb1    vfat      1.8G  2.0K  1.8G   1% /run/media/liveuser/SanDisk
and the first element reports that the target device is represented as /dev/sdb1.
Write down your target in the format, /dev/sd?1, where ? is likely to be b, c, d or e.

Unmount the target USB stick - edit to reflect your target:

umount /dev/sd?1

For a nominal 2GB stick, enter this command - edit to reflect your target:

su -c "livecd-iso-to-disk --reset-mbr --overlay-size-mb 500 --home-size-mb 800 --unencrypted-home /run/initramfs/livedev /dev/sd?1" 

Writing the stick will take some time, and when successful will finish by reporting

"Target device is now set up with a Live image!"

Your persistent Sugar on a Stick is ready to run.

Shut down your "host" Sugar LiveOS media system and boot the new.

For a nominal 4GB stick use this command,

su -c "livecd-iso-to-disk --reset-mbr --overlay-size-mb 1000 --home-size-mb 1600 --unencrypted-home /run/initramfs/livedev /dev/sd?1"

Maintenance

The persistent overlay status may be queried by issuing this command on the live system:

   dmsetup status live-rw 

The returned value may look like this:

live-rw: 0 8388608 snapshot 42296/204800 176

where the fraction after 'snapshot' for the logical volume is that of 512-byte sectors consumed in the overlay.