Package provide an old Apache 2.2 configuration in /etc/apache2/modules.d/99_nagios3.conf. The default provided still use old authz_host config "Order" instead of the new Apache 2.4 "Require", making it not to work out of the box. Version 4.1.1 is okay, didn't test versions in between though.
We can't really fix this for the existing nagios-3.5.1 ebuilds because they're marked stable. We would have to make a new revision, then wait a month, and stabilize the new revision. I eventually plan to "fix" this by stabilizing nagios-4.x (now that apache-2.4.x is stable) and then removing the nagios-3.x stuff.
Apache-2.4 is still unstable on ~hppa ~ppc ~ppc64, and ~x86 where nagios-3.5.x is stabilized. I can put in the stabilization request for nagios-4.x as soon as that gets taken care of in bug #468302. If you can, I would suggest upgrading to nagios-4.x now by adding net-analyzer/nagios-4.1.1 and net-analyzer/nagios-core-4.1.1 to your package.accept_keywords. Most of what nagios actually does is provided by the plugins, and your nagios-plugins don't need to be updated, so the migration should be pretty easy. Otherwise, if you wait until we get this all sorted out, nagios-4.1.1 will go stable (and I'll remove 3.5.1) and you'll have to upgrade anyway =)
Thank you for your quick answer. The change needed is quite trivial. I modified the Wiki to reflect the 2 lines modifications needed. https://wiki.gentoo.org/wiki/Nagios/Guide#Restricting_Access_to_the_Nagios_Web_Interface Would it take some stabilization to include a warning in the ebuild in meantime? I went for 4.1.1 anyway as i thought version 3.5.1 is rather old. I'm still in the process of configuring mine to include all the plugins i need. Yet i didn't encounter problems with any plugins so far. I am not surprised, after all, it's simply calling scripts. The only one i am worried about is the nagios-virt, because it's in C and rather old. In any case. Thank you again. If i can be of any further help, don't hesitate writing me.
(In reply to Simon-Pierre Dubé from comment #3) > Thank you for your quick answer. > > The change needed is quite trivial. I modified the Wiki to reflect the 2 > lines modifications needed. > Thanks for doing that! It is indeed pretty easy to fix, but we only get to install one config file at a time -- that's why nagios-4.x now requires apache-2.4.x. > > Would it take some stabilization to include a warning in the ebuild in > meantime? > Normally adding an "ewarn" message would be safe, but I just tried to do it, and there's something messed up in the ebuild. The nagios-core-3.5.1.ebuild has *two* definitions of pkg_postinst()... the first one has a lot of nice logic and informational messages and all that stuff. That's where I tried to add the ewarn (so that it would only show up for people with USE="apache2 web"). The second pkg_postinst() was added by accident and only fixes some permissions. But it overwrites the first definition! To fix it, I would delete the second pkg_postinst() and move its code into the first one. But, that would actually constitute a fairly large change, since the whole big function (now shadowed) would just "appear"... and we can't make big changes to stable ebuilds. (The other thing I could do is copy a bunch of logic into the second pkg_postinst, but I'd rather not do that either.) tl;dr yes we could do it, just not in this case. Sorry!
Nagios 3.5.1 has old security vulnerabilities and will be removed from the tree ASAP (we're just waiting on some lagging arches to handle their keyword requests).