In the chain of updating Xorg I had to update serveral ports and by accident, I also included net-mgmt/nagvis. This port stores its etc/ folder under /usr/local/www/nagvis/etc. The folder contains maps and other crucial configuration stuff. An update, reinstallation DESTROYS (or overwrites, but with the very same end result) all content of maps, automaps! Other ports store either their local configs in ETCDIR=/usr/local/etc or preserve the configs. I had a bunch of maps created my own and after this update, everything was gone, even the customisation of integration of nagvis in net-mgmt/icingaweb2. This is very bad. Even if someone does have a backup, this shouldn't be happen. Either the content of this non-standard etc folder should be precious and not deleted, or the standard etc folder should be delegated to /usr/local/etc/nagvis (or whatever is suitable in this case). Or do I miss something here and made a capital mistake? oh
I'm completely clouded :-( Sorry for the noise, checked on the wrong machine! There is no(!) destruction. But anyway, if there is a possibility to delegate etc/ to /usr/local/etc/nagvis would be great.