CopyFileSystem

Differences between revisions 2 and 3
⇤ ← Revision 2 as of 2005-11-02 15:19:36 →
Size: 975
Editor: 194_220_103_66-WIFI_HOTSPOTS
Comment: fix LP link
← Revision 3 as of 2005-11-02 16:43:55 → ⇥
Size: 2929
Editor: 209
Comment: use cases and remainder of BOF notes (rough)
Deletions are marked like this. Additions are marked like this.
Line 16: Line 16:
 * A user has installed extra packages in the live session and wants them to be there in the installed system too.
 * A user has been messing about with the live session and wants a clean installation so that they can start from scratch.
 * A user has spent some time customizing their settings (static network configuration? desktop preferences?) and wishes for them to be preserved.
 * A user has already saved documents and wants to preserve them in the installed system.
Line 29: Line 34:
-> From the BOF:
Line 31: Line 35:
* How to transfer data from the ubuntu account?
* Create a casper unwind script in casper itself?		  * How to transfer data from the ubuntu account?
 * Create a casper unwind script in casper itself?

{{{
Even if we copy unmodified filesystem, need to copy over some other files:
 - /etc/X11/xorg.conf (and md5sum) (difficult and risky to re-probe)
  - xserver-xorg must have an interface to reset the saved md5sum
 - /etc/network/interfaces
 - gnome-panel configuration
 - casper logs
should have casper drop in hooks for each thing that needs to be re-done

copying dotfiles is difficult (ubuntu username hardcoded in evolution gconf settings at least, possibly arbitrary other things)

must make it clear in the UI either way; also document what will happen on the CD sleeve

what happens if the user makes changes while the filesystem is being copied? (answer: argh, good reason to copy unmodified filesystem in order not to melt our brains)

deal with extra package installations:
 - reinstall any language packs selected in the language selector?
 - dpkg --get-selections in live filesystem, dpkg --set-selections; apt-get dselect-upgrade in installed system?
  - no removal support?
  - non-fatal if it fails

considered filesystem-level or file-level copy; file-level lets us deal with different filesystems, non-resizable filesystems, etc.

don't automatically reboot at end of installation, to give user a chance to copy over any documents they explicitly want to keep

defer any handling of desktop preferences until future; needs explicit support in desktops, and runs into problems with programs that hardcode usernames / absolute paths / etc.
}}}

Summary

The copying component is largely trivial, though it has been proposed that it would be useful to allow the user to choose whether to copy the pristine filesystem, or the version which has been modified during the session. If the modified filesystem is copied, some of the modifications made to it by casper must be reversed. This needs more discussion.

Rationale

Use cases

  • A user has installed extra packages in the live session and wants them to be there in the installed system too.
  • A user has been messing about with the live session and wants a clean installation so that they can start from scratch.
  • A user has spent some time customizing their settings (static network configuration? desktop preferences?) and wishes for them to be preserved.
  • A user has already saved documents and wants to preserve them in the installed system.

Scope

Design

Implementation

Code

Data preservation and migration

Outstanding issues

BoF agenda and discussion

  • How to transfer data from the ubuntu account?
  • Create a casper unwind script in casper itself? 

Even if we copy unmodified filesystem, need to copy over some other files:
 - /etc/X11/xorg.conf (and md5sum) (difficult and risky to re-probe)
  - xserver-xorg must have an interface to reset the saved md5sum
 - /etc/network/interfaces
 - gnome-panel configuration
 - casper logs
should have casper drop in hooks for each thing that needs to be re-done

copying dotfiles is difficult (ubuntu username hardcoded in evolution gconf settings at least, possibly arbitrary other things)

must make it clear in the UI either way; also document what will happen on the CD sleeve

what happens if the user makes changes while the filesystem is being copied? (answer: argh, good reason to copy unmodified filesystem in order not to melt our brains)

deal with extra package installations:
 - reinstall any language packs selected in the language selector?
 - dpkg --get-selections in live filesystem, dpkg --set-selections; apt-get dselect-upgrade in installed system?
  - no removal support?
  - non-fatal if it fails

considered filesystem-level or file-level copy; file-level lets us deal with different filesystems, non-resizable filesystems, etc.

don't automatically reboot at end of installation, to give user a chance to copy over any documents they explicitly want to keep

defer any handling of desktop preferences until future; needs explicit support in desktops, and runs into problems with programs that hardcode usernames / absolute paths / etc.

UbuntuExpress/CopyFileSystem (last edited 2008-08-06 16:35:01 by localhost)