Universal Blue•3y ago

Yes that's what I was saying > It doesn’t attempt to understand the contents of files – if you have

Yes that's what I was saying

It doesn’t attempt to understand the contents of files – if you have modified a config file in any way, that wins

akdev•5/14/23, 2:34 AM

Mm you're right

Ppythoner6 Yes that's what I was saying > It doesn’t attempt to understand the contents of ...

Arcitec•5/14/23, 2:34 AM

I read elsewhere that it's running a patch/diff, similar to this: Generate a patch between your

/usr/etc/

/usr/etc/

and the new deployment's

/usr/etc/

/usr/etc/

and then apply those patches to your

/etc/

/etc/

and just ignore the ones that failed to apply.

akdev•5/14/23, 2:35 AM

Not sure why he calls it a 3-way merge though if it is not merging anything

Arcitec•5/14/23, 2:35 AM

Yeah that blog is a mess of mixed up terms.

Arcitec•5/14/23, 2:36 AM

Official docs are here and they mention the thing I just said: https://ostreedev.github.io/ostree/deployment/

pythoner6OP•5/14/23, 2:37 AM

https://github.com/ostreedev/ostree/blob/16cb47489e582da9c139fee20acdac7079867843/docs/atomic-upgrades.md?plain=1#L76

GitHub

ostree/atomic-upgrades.md at 16cb47489e582da9c139fee20acdac70798678...

Operating system and container binary deployment and upgrades - ostree/atomic-upgrades.md at 16cb47489e582da9c139fee20acdac7079867843 · ostreedev/ostree

Ppythoner6 https://github.com/ostreedev/ostree/blob/16cb47489e582da9c139fee20acdac707986784...

Arcitec•5/14/23, 2:37 AM

But read this from the OSTree website:

When OSTree creates a deployment, it performs a 3-way merge using the old default configuration, the active system’s /etc, and the new default configuration. In the final filesystem tree for a deployment then, /etc is a regular writable directory.

pythoner6OP•5/14/23, 2:37 AM

How it works is:
Files in the currently booted deployment's
/etc
/etc
which were modified from the default (of the same deployment) are retained.
Files in the currently booted deployment's
/etc
/etc
which were not modified from the default (of the same deployment) are upgraded to the new defaults from the new deployment's .

Arcitec•5/14/23, 2:38 AM

Why does their own website contradict the part you just quoted?

pythoner6OP•5/14/23, 2:39 AM

I don't think it's a contradiction do much as ambiguous use of the term "merge"

Arcitec•5/14/23, 2:39 AM

Yeah it could just be poorly explained. Grr.

pythoner6OP•5/14/23, 2:39 AM

Individual files aren't being merged, but the entire /etc tree is being merged in a very coarse grained way

Arcitec•5/14/23, 2:40 AM

Oh yeah that makes sense. What a poor way to phrase that on their site. I've always thought it did a 3-way merge per-file, not directory-wise.

Arcitec•5/14/23, 2:40 AM

I've never even thought of directory comparisons as "3-way merging".

pythoner6OP•5/14/23, 2:41 AM

Yeah it's definitely not the best way to explain it without a bit more detail

Arcitec•5/14/23, 2:41 AM

Yeah, thanks for finding that, it's very useful to know. That changes how I'll maintain my system. I will run the "config diff" more often to resolve actual changes.

pythoner6OP•5/14/23, 2:42 AM

It's probably just a case of the people writing the docs being familiar enough with how it works that the explanation seems obvious enough - even though it's a bit unclear without the extra detail to someone not as familiar.

Arcitec•5/14/23, 2:43 AM

Yeah it's a common curse when trying to document a complex system that you're very familiar with.

pythoner6OP•5/14/23, 2:43 AM

Yeah my plan is to try to avoid touching things in /etc at all where possible

AArcitec Yeah, thanks for finding that, it's very useful to know. That changes how I'll m...

akdev•5/14/23, 2:43 AM

it'd be cool to have a script that does this and notifies

Arcitec•5/14/23, 2:43 AM

Yep, one thing I always do is edit the wireplumber config to add a script that disables audio device sleeping, to avoid that silent "popping" whenever audio begins playing again. I am doing it via some big edits.

I've been meaning to look for a way to install that in a more granular way that doesn't need maintenance constantly whenever wireplumber changes config.

Aakdev it'd be cool to have a script that does this and notifies

Arcitec•5/14/23, 2:44 AM

Yeah good idea, some kinda GUI that runs as autostart on login and pops up if there's changes.

dreams

pythoner6OP•5/14/23, 2:44 AM

Yeah I think having some kind of automated check that can keep tabs on the diff to prevent drift would be interesting

akdev•5/14/23, 2:44 AM

you don't really need a gui, just run the command if there are changes send a dbus notification

pythoner6OP•5/14/23, 2:44 AM

A bit complicated because there's a bunch of things that are probably going to be changed just by installing though, like /etc/passwd

Aakdev you don't really need a gui, just run the command if there are changes send a db...

Arcitec•5/14/23, 2:44 AM

Great idea

Ppythoner6 A bit complicated because there's a bunch of things that are probably going to b...

akdev•5/14/23, 2:45 AM

I wish anaconda put this stuff in /usr/etc before commiting the deployment to disk...

pythoner6OP•5/14/23, 2:46 AM

Eh but then should you be ending up with a new ostree deployment every time you change your password?

Arcitec•5/14/23, 2:47 AM

I don't think it compares those files, like and . That would be bad.

pythoner6OP•5/14/23, 2:48 AM

Arcitec•5/14/23, 2:48 AM

W!!@ADD

Arcitec•5/14/23, 2:48 AM

That's dumb.

akdev•5/14/23, 2:48 AM

yeah they do appear as they are not in /usr/etc

Ppythoner6 Eh but then should you be ending up with a new ostree deployment every time you ...

akdev•5/14/23, 2:48 AM

I'd be okay with that but there are some implications ...

akdev•5/14/23, 2:49 AM

but I would like it if does not destroy the system

akdev•5/14/23, 2:49 AM

conceptually that should reset the system to default state

Aakdev I'd be okay with that but there are some implications ...

pythoner6OP•5/14/23, 2:50 AM

Yeah, in a future where things are more image based "native" I could see something along those lines being the case

Aakdev yeah they do appear as they are not in /usr/etc

pythoner6OP•5/14/23, 2:53 AM

I do see a /usr/etc/passwd and /usr/etc/shadow etc, but there's no passwords for any accounts, so a little hard to log in if things got reset to that

(unless there's something that goes through the first boot setup again or something?)

akdev•5/14/23, 2:54 AM

pretty sure your system is bricked

akdev•5/14/23, 2:54 AM

if you remove them

ragectl•5/14/23, 2:54 AM

yeah those files under /usr are probably only there to fix file not found errors

akdev•5/14/23, 2:55 AM

there are actual defaults for these files, wonder why those aren't used

akdev•5/14/23, 2:56 AM

ragectl•5/14/23, 2:56 AM

I could see a future state where /etc/shadow /etc/group /etc/passwd actually become directories which get

include

include

-d

akdev•5/14/23, 2:56 AM

that cannot happen, it breaks POSIX

akdev•5/14/23, 2:56 AM

systemd has some sysusers thing tho

ragectl•5/14/23, 2:57 AM

not everything sticks to POSIX

akdev•5/14/23, 2:57 AM

the last 45 years or so of tooling assume that all your users are in /etc/passwd

akdev•5/14/23, 2:57 AM

this convention probably even predates POSIX

akdev•5/14/23, 2:58 AM

there's realistically no way we're going to change that imo