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Re: Moving rc.d scripts to base.tgz



On Sun, Apr 17, 2011 at 10:48:25AM +0000, Michael van Elst wrote:
 > jmmv%julipedia.org@localhost (Julio Merino) writes:
 > 
 > >The fact that these things are not configurable nicely, other than by
 > >editing hardcoded values, is a result of these scripts trying to be
 > >generic but not really being because people is supposed to edit them
 > >in place.  This is not the result of a nice design.
 > 
 > The nice design is to keep such checks easily edible. Instant flexibility
 > instead of limited choices chosen by the designers.

No, because then you have to write shell script (or worse, hack
someone else's) to get the behavior you want. This limits the
flexibility to people who have sufficient skills to do that (and who
trust that skill enough to do it in a production context...)

Also, configuration should not in general be Turing-complete, because
that makes it too hard to reason about and debug. In this business we
tend to make configuration Turing-complete when we don't know the
range of sensible configurations yet or if that range is extremely
large. Hence, for example, sendmail.cf. However, as the environment
matures the unanswered questions tend to get answered, the outlier
situations requiring weird configs tend to go away, and eventually the
Turing-completeness becomes a liability. Hence, in the same example,
Postfix.

I should think we can figure out how to make /etc/daily sufficiently
flexible that no ordinary sysadmin should ever need to edit it.

-- 
David A. Holland
dholland%netbsd.org@localhost


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