The initramfs hook in the initramfs-tools-ubuntu-core package includes the following:
# Extra stuff we need
mkdir -p "$DESTDIR/etc/system-image/"
cp /etc/system-image/archive-master.tar.xz "$DESTDIR/etc/system-image/"
cp /etc/system-image/archive-master.tar.xz.asc "$DESTDIR/etc/system-image/"
copy_exec /bin/chown
copy_exec /bin/tar
copy_exec /usr/bin/gpg
copy_exec /usr/bin/system-image-upgrader
copy_exec /usr/bin/unxz
The i-t-u-c package does not depend on any of the packages providing these files; which means that installing i-t-u-c without installing, e.g., the package that provides /etc/system-image/archive-master.tar.xz , can break initramfs upgrades for the system.
It's also not clear to me why the upgrade is being done from the initramfs. My understanding was that Stéphane had proposed that the update should be done from the running system using a namespace-specific rw remount of the rootfs (preventing processes other than the upgrader from writing to the disk). This would enable the update to be applied with only a single reboot. With the proposed script, another reboot is still required in order to fully apply the update because the update may change the running kernel. (Which means that the current script is buggy, because it doesn't reboot at the end - it just leaves the system mounted rw and boots into it.)
Hi Steve,
Immediate problem fixed, pending upload by someone with appropriate powers :-)
> My understanding was that Stéphane had proposed that the update should be done from the running system using a
> namespace-specific rw remount of the rootfs...
The blueprint does mention this as an idea (using the words 'may' and 'might'), so it sounds like we need to discuss if that is the approach we want to take, and then flesh out work items as appropriate.