Manually reset of modified /etc files to current ostree commit

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Greetings @ldvp,

Let me summarize to make sure I understand the situation here.

  • You start with a base TorizonCore image I assume.
  • You make some modifications then capture these changes with TorizonCore Builder to create a new version. (release 1)
  • With release 1 you make manual changes to /etc. These manual changes are not officially part of any release, 1 or 2, is that right?
  • You then make a new version (release 2). Just to clarify is release 2 based on release 1? Also are the manual changes to /etc included in release 2? I assume based on your wording they are not.
  • Now the problem is that when you deploy release 2 the manual changes done to release 1 are still present and not overwritten by release 2.

Did I get that all correct?

If I did then it sounds like you are falling victim to a fundamental “feature” of OSTree. OSTree treats the /etc directory differently than other directories. The behavior is summarized in this excerpt from the OSTree documentation:

On upgrade, OSTree will perform a basic 3-way diff, and apply any local changes to the new copy, while leaving the old untouched.

So there’s a 3 way merge happening here between release 1’s /etc contents, the manual changes done to /etc, and release 2’s /etc contents. This sounds like what you’re experiencing.

Now if I understand you basically want to to remove the manual changes done to /etc so that the update goes from release 1 to release 2 cleanly. I don’t believe there’s a OSTree command that resets /etc. However there’s another mechanism you can do. In order to do the 3 way merge OSTree needs to know release 1’s original /etc content. But how does it do that if you do manual changes on /etc? The secret is /usr/etc, this directory is a read only default of that release’s /etc.

For your case what this means is that /usr/etc should contain release 1’s original /etc content without any of the changes that occurred after release 1 was deployed. I imagine you can do a kind of magic with rsync to copy/overwrite /usr/etc to /etc to effectively “restore” it, to it’s original state.

Let me know if this helps you.

Best Regards,
Jeremias

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