Re: Parsing of pg_hba.conf and authentication inconsistencies

Magnus Hagander <magnus(at)hagander(dot)net> writes:
>> The good way to solve this would be to have independant command line
>> utilities which check pg_hba.conf, pg_ident.conf and postgresql.conf for
>> errors. Then DBAs could run a check *before* restarting the server.

> While clearly useful, it'd still leave the fairly large foot-gun that is
> editing the hba file and HUPing things which can leave you with a
> completely un-connectable database because of a small typo.

That will *always* be possible, just because software is finite and
human foolishness is not ;-).

Now, we could ameliorate it a bit given a "postgres --check-config"
mode by having pg_ctl automatically run that mode before any start,
restart, or reload command, and then refusing to proceed if the check
detects any indubitable errors. On the other hand, that would leave
us with the scenario where the checking code warns about stuff that it
can't be sure is wrong, but then we go ahead and install the borked
config anyway. (Nobody is going to put up with code that refuses
to install config settings that aren't 100% clean, unless the checks
are so weak that they miss a lot of possibly-useful warnings.)

Seems a lot better to me to just train people to run the check-config
code by hand before pulling the trigger to load the settings for real.

regards, tom lane