Re: location of the configuration files - Mailing list pgsql-hackers

Peter Eisentraut wrote:
> Tom Lane writes:
> 
> > I would favor a setup that allows a -C *directory* (not file) to be
> > specified as a postmaster parameter separately from the -D directory;
> 
> A directory is not going to satisfy people.

Who is asking to put postgresql.conf, pg_hba.conf, and pg_ident.conf in
different directories?  I haven't heard anyone ask for that.

> > I don't see any great value in a separate postgresql.conf parameter for
> > each secondary config file; that just means clutter to me,
> 
> Not to other people.
> 
> > 1. No -C switch, no -D switch, no PGDATA found in environment: seek
> > postgresql.conf in the default -C directory established at configure
> > time.  Use the 'datadir' specified therein as -D.  Fail if postgresql.conf
> > doesn't define a datadir value.
> 
> OK.
> 
> > 2. No -C switch, no -D switch, PGDATA found in environment: use $PGDATA
> > as both -C and -D.
> 
> This behavior would be pretty inconsistent.  But maybe it's the best we
> can do.

What happens if postgresql.conf then defines data_dir?  Seems we ignore it.

This brings up the same issue of whether -C/PGCONFIG is a inferior
option to -D/PGDATA, and whether we keep the config files in /data by
default.

> > 3. No -C switch, -D switch on command line: use -D value as both -C and -D,
> > proceed as in case 2.
> 
> Same as above.


> 
> > 4. -C switch, no -D switch on command line: seek postgresql.conf in
> > -C directory, use the datadir it specifies.
> 
> OK.

Here we are saying the -C doesn't override postgresql.conf as the proper
PGDATA value.  Is that what we want?  We had the question above over how
a data_dir in postgresql.conf is handled.

> 
> > 5. -C and -D on command line: seek postgresql.conf in -C directory,
> > use -D as datadir overriding what is in postgresql.conf (this is just
> > the usual rule that command line switches override postgresql.conf).
> 
> But that usual rule seems to be in conflict with cases 2 and 3 above.
> (The usual rule is that a command-line option overrides a postgresql.conf
> parameter.  The rule in 3, for example is, that a command-line option (the
> same one!) overrides where postgresql.conf is in the first place.)


Yes, the big question seems to be if we are defaulting -C to be the same
as -D, whether that is an actual specification of -D that should
override postgresql.conf.

This is part of the reason I don't like the -D assumes -C and stuff like
that.

I think we need to move the config files to pgsql/etc, for backup and
initdb safety, and move toward having PGCONFIG/-C as the driving
parameter.  I think having both function equally and defaulting if the
other is not specified is going to breed confusion.

I am willing to make thing a little difficult for backward compatibility
to do this, and I think because it is only administrators, they will
welcome the improvement.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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