Re: BUG #6353: If there is invalid line in pg_hba.conf, DB start fails without any nofice and no logs in pgstartup.

erkan(at)eurotel(dot)com(dot)tr writes:
> If I add this line to pg_hba.conf, it causes a silent startup failure:
> local all backup 127.0.0.1/32 trust
> There is a linux user backup on this system. After adding this line and
> issue "pg_ctl reload" it signals server successfully, no errors. But if I
> stop db server, I can not start db anymore. Strangely no log exists in
> pgstartup.log.

Well, that line is obviously incorrect, because a "local" line doesn't
need an IP address. For me, the postmaster gives very clear warnings
about this, either in the pg_ctl reload case:

LOG: received SIGHUP, reloading configuration files
LOG: invalid authentication method "127.0.0.1/32"
CONTEXT: line 95 of configuration file "/var/lib/pgsql/data/pg_hba.conf"
WARNING: pg_hba.conf not reloaded

or in the fresh-start case:

LOG: invalid authentication method "127.0.0.1/32"
CONTEXT: line 95 of configuration file "/var/lib/pgsql/data/pg_hba.conf"
FATAL: could not load pg_hba.conf

Your problem apparently is that the log messages are either not coming
out at all, or you're looking in the wrong place for them. You have not
said anything about your logging configuration so it's hard to give
concrete advice, but in the default configuration set up by Red Hat's
packages I'd expect those messages to appear in the current log file
underneath /var/lib/pgsql/data/pg_log/. It's also conceivable that the
messages aren't getting out at all because of a permissions-type problem
--- I remember some very old versions of selinux policy would sometimes
block postgres log messages, for example. If you've got selinux enabled
it'd be worth checking for avc messages in the kernel logs.

regards, tom lane