Horton

Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])

Andres Freund <andres@2ndquadrant.com>

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From: Andres Freund <andres@2ndquadrant.com>
To: Stephen Frost <sfrost@snowman.net>
Cc: Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Bruce Momjian <bruce@momjian.us>, Amit Kapila <amit.kapila16@gmail.com>, Martijn van Oosterhout <kleptog@svana.org>, Alvaro Herrera <alvherre@2ndquadrant.com>, Dimitri Fontaine <dimitri@2ndquadrant.fr>, Josh Berkus <josh@agliodbs.com>, Fujii Masao <masao.fujii@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2013-08-30T13:06:27Z
Lists: pgsql-hackers 
On 2013-08-29 21:26:48 -0400, Stephen Frost wrote:
> > Sure, you can construct a scenario where this matters.  The ops guys
> > have "sudo postgres pg_ctl" access but adminpack isn't installed and
> > they have no other way to modify the configuration file.  But that's
> > just bizarre.  And if that's really the environment you have, then you
> > can install a loadable module that grabs ProcessUtility_hook and uses
> > it to forbid ALTER SYSTEM on that machine.  Hell, we can ship such a
> > thing in contrib.  Problem solved.  But it's surely too obscure a
> > combination of circumstances to justify disabling this by default.
> 
> It's not the OPs guy that I'm worried about using ALTER SYSTEM- I don't
> expect them to have any clue about it or care about it, except where it
> can be used to modify things under /etc which they, rightfully, consider
> their domain.

I think for the scenarios you describe it makes far, far much more sense
to add the ability to easily monitor for two things:
* on-disk configuration isn't the same as the currently loaded (not
  trivially possible yet)
* Configuration variables only come from locations that are approved for
  in your scenario (Already possible, we might want to make it even easier)

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
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