Re: etc-overrides-non-etc configuration file model [Re: RFC: OpenRC as Init System for Debian]
Don Armstrong d...@debian.org writes: On Thu, 10 May 2012, Gergely Nagy wrote: FWIW, /etc/default/* and /etc/$package/conf.d/* and similar already do something *very* close to what etc-overrides-non-etc does. To the point that changing a file under /etc/default, or adding a snippet to conf.d/ can break just as well when the underlying default changes as if that upstream happened to be outside of /etc. That's true. I suspect that much of conf.d/* and default/* are a consequence of the lack of easy 3-way merge support in dpkg. But that's kind of an orthogonal issue. I don't think that is so. It's also there to allow other packages to drop snippets there. Modifying another package's conffile would be against the policy, so conf.d/-style snippets are the obvious solution. Nothing to do with the lack of merge in this case. Even if dpkg gains fabulous merge support that never fails, ever, conf.d/ will still be used because we need the ability to add snippets from unrelated packages. Except it's easier to follow, since the default is never modified by the admin, while if it's in /etc too, like in plenty of cases in the archive, both can change, and we end up with even scarier situations that can't be resolved sanely. I'm unable to follow. In the etc-overrides-non-etc case, we would be increasing the number of cases where we had copies in /etc and in non-etc. If things were just in /etc, they wouldn't be in non-etc, and you'd only have one copy in all cases. True, if the non-etc stuff were simply copied, we'd have a single copy. With all the disadvantages that brings, like not being able to override the default from another package, as that would mean we have to modify a configuration file. In the case of systemd, you need to be able to override the default from another, unrelated package. At least for things like the syslog service. At the moment, systemd has /lib/systemd/system/syslog.service, which starts the journal. If I want to override that, I need to override the syslog.service, which is done by placing a file in /etc/systemd/system/syslog.service (whether a symlink, or a file, doesn't matter; the syslog daemons in debian place a symlink). If we didn't have etc-overrides-lib, how would you do this? How would you make it able to override a single service, from another package? Play dpkg-divert tricks? Or use conf.d/-style stuff? The latter suffers from the same issue etc-overrides-non-etc suffers from, the former makes it much harder for admins to override services, and I don't like the idea of dpkg-divert'ing config files all over the place either.. -- |8] -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/873977s1lq@luthien.mhp
Re: etc-overrides-non-etc configuration file model [Re: RFC: OpenRC as Init System for Debian]
Don Armstrong d...@debian.org writes: On Thu, 10 May 2012, Uoti Urpala wrote: Don Armstrong wrote: The reason why it is relevant is because [...] I don't see how the following would make this comparison with rpm relevant. This is debian-devel, and we're talking about configuration file handling in Debian, which makes ucf and dpkg relevant. Having configuration files in /etc and using ucf or similar enables you to deal with this problem easily. Yes, you do need some tool improvements to be able to alert the user about changes. Right. So for every package which does this, you have to check to see whether a configuration file in /etc has had it's corresponding non-etc configuration file changed, and then offer to merge them together. FWIW, /etc/default/* and /etc/$package/conf.d/* and similar already do something *very* close to what etc-overrides-non-etc does. To the point that changing a file under /etc/default, or adding a snippet to conf.d/ can break just as well when the underlying default changes as if that upstream happened to be outside of /etc. We do not handle that case either, and I don't see how the default being outside of /etc would be any different. Except it's easier to follow, since the default is never modified by the admin, while if it's in /etc too, like in plenty of cases in the archive, both can change, and we end up with even scarier situations that can't be resolved sanely. So there's basically no advantage to etc-overrides-non-etc unless one hasn't bothered to implement proper configuration file handling. Then we already have a problem, because the conf.d/ and default stuff suffer from the same problems, and they're used widely all over the place. -- |8] -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/87vck3de3i@luthien.mhp
Re: etc-overrides-non-etc configuration file model [Re: RFC: OpenRC as Init System for Debian]
On Thu, 10 May 2012, Gergely Nagy wrote: FWIW, /etc/default/* and /etc/$package/conf.d/* and similar already do something *very* close to what etc-overrides-non-etc does. To the point that changing a file under /etc/default, or adding a snippet to conf.d/ can break just as well when the underlying default changes as if that upstream happened to be outside of /etc. That's true. I suspect that much of conf.d/* and default/* are a consequence of the lack of easy 3-way merge support in dpkg. But that's kind of an orthogonal issue. Except it's easier to follow, since the default is never modified by the admin, while if it's in /etc too, like in plenty of cases in the archive, both can change, and we end up with even scarier situations that can't be resolved sanely. I'm unable to follow. In the etc-overrides-non-etc case, we would be increasing the number of cases where we had copies in /etc and in non-etc. If things were just in /etc, they wouldn't be in non-etc, and you'd only have one copy in all cases. Don Armstrong -- a friend will help you move a best friend will help you move bodies but if you have to move your best friend's body you're on your own -- a softer world #242 http://www.asofterworld.com/index.php?id=242 http://www.donarmstrong.com http://rzlab.ucr.edu -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20120510220412.gg3...@rzlab.ucr.edu
