Quoting Steven M. Bellovin (smb@research.att.com):
> In message <200206251902.g5PJ2Pm11783@toad.rmkhome.com>, Rick Kelly writes:
> >When I set up a system I use the policy that stuff in /etc/rc.d is
> >the basic system stuff and shouldn't be messed with.
> 
> This is crucial.  Updating /etc is the most difficult -- and 
Concur

...
> /etc.local/rc.d might be a better solution.  Generalize as needed for 
> other files that need to be customized...

Can I vote for /etc/rc.local.d/ or even /usr/local/etc/rc.d/
rather than ANOTHER top level dir to maintain?  On other BSD's,
I've created local versions of everything that override the
"system" variables.  rc.local ran after rc.  sysctl.conf.local
overrides sysctl.conf, etc.

I try to leave the system config files alone and add to them with
local ones that "make install" doesn't wipe out.

services, protocols, group, passwd and such obviously don't allow
that shy of an external name service (NIS, LDAP, Hesiod, etc).  Pity.