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Quirky: another recovery mechanism

February 13, 2014 — BarryK
Quirky already has two recovery mechanisms:

  • Uninstalling of packages is very clever, rolling back to the situation before the package was installed. Or, retaining files installed by later-installed packages.

  • The snapshot mechanism will roll the entire installation back to when the snapshot was taken.


  • I had a third mechanism in mind, and have only now created the infrastructure for it. I want to be able to do two different things: completely rebuild a broken installation, and write a Quirky Installer application that will install your currently-running Quirky to any other drive or partition.

    The install scripts, 'install-quirky-to-drive.sh' and 'install-quirky-to-partition.sh', now convert the downloaded file, for example 'tahr-6.0.5.usfs.xz' into a normal Squashfs file 'tahr-6.0.5.sfs' and store it at /audit/reference in the new installation of Quirky.

    Note, if the install scripts are not used, for example the 'tahr-6.0.5-8gb.img.xz' file is used to write directly to a Flash stick, then there will be nothing in /audit/reference. In that case, a special "reference snapshot" is made at first boot, which creates /audit/reference/tahr-6.0.5.sfs.

    The Package Manager now saves all installed packages in /audit/packages, and deletes them if a package is uninstalled.

    This is just the infrastructure, applications to do something with it have yet to be written.

    Comments

    luufs"Iguleder"Barry, I think writing your own file system on top of FUSE could be a more elegant solution - I wrote a simple union file system with two layers, https://github.com/iguleder/luufs this way.

    # ls -l
    total 264072
    -rw-r--r-- 1 root root 2946247 Feb 20 20:17 201402202012_201402201111.xdelta
    -rw-r--r-- 1 root root 267460608 Feb 20 20:16 201402202012.sfs

    Tags: linux