More robust iso

Summary
Make SoaS .isos more robust by removing the compressed CoW indirection layer for root fs / sole partition.

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Current status

 * Targeted release: SoaS v4
 * Last updated: Mchua 18:36, 11 June 2010 (EDT)
 * Percentage of completion: 0%

Detailed Description
SoaS sticks regularly fail in an irrecoverable manner after a certain volume of writes to the image; when the overlay runs out of storage, it corrupts the entire overlay the compressed ext3 filesystem fails when the overlay runs out of storage.

normal fs = "sorry, can't write your file that you just tried to write cause the disk is full"

overlay fs = "sorry, can't write your file and I just corrupted everything you ever wrote to the overlay".

Our current thinking is that this goal is achievable with a bit of scripting that takes the livecd-tools .iso image we get now and...


 * 1) creates a pre-partitioned disk image (cue loads of partition / cylinder /etc. nuances here)
 * 2) unrolls the livecd-tools' nested filesystems and copies the contents to the disk image from #1
 * 3) does any hacking of the filesystem contents necessary to remove any undesirable assumptions about the livecd-tools' filesystem configuration.

Benefit to SoaS
SoaS stick failure is inevitable after a certain volume of writes right now because the overlay will run out of the finite amount of space it has. This eliminates this method of stick failure.

#1798 is the relevant ticket.

Scope
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UI Design
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User Experience
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Dependencies
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Contingency Plan
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Documentation
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The below links are not sorted, but are here for reference when this feature proposal is being written up in more detail. Not all of them may be useful, as a warning for the next person to tackle this page. Mchua 19:04, 11 June 2010 (EDT)


 * http://cgit.sugarlabs.org/soas/mainline/tree/make_fake_device.sh?h=blueberry#n44
 * http://lists.sugarlabs.org/archive/soas/2010-January/000715.html
 * http://lists.sugarlabs.org/archive/soas/2010-January/000654.html
 * http://cgit.sugarlabs.org/soas/mainline/tree/livecd-iso-to-bootable-tree.sh?h=blueberry
 * http://lists.sugarlabs.org/archive/soas/2010-January/000656.html
 * http://lists.sugarlabs.org/archive/soas/2010-January/000683.html

Release Notes
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