Re: source of connection fails at pg startup?

On 05/21/2018 10:48 PM, Stuart McGraw wrote:
> When I start my postgresql server I get 11 messages reporting that
> "password
> authentication failed for user 'postgres'" spaced about ~.5sec apart.
> I increased the logging level to INFO, and added the application name to
> the
> message format (after the pid) which resulted in:
>
>   2018-05-21 23:04:44.395 MDT [20232][[unknown]] [unknown](at)[unknown]
> LOG:  connection received: host=[local]
>   2018-05-21 23:04:44.395 MDT [20232][[unknown]] postgres(at)postgres
> FATAL:  password authentication failed for user "postgres"
>   2018-05-21 23:04:44.395 MDT [20232][[unknown]] postgres(at)postgres
> DETAIL:  Password does not match for user "postgres".
>     Connection matched pg_hba.conf line 90: "local   all   all   md5"
>
> This is on a Ububuntu-18.04 machine with postgresql-10.3 from Ubuntu.
> As distributed
> the pg_hba.conf line mentioned used "peer" authentication method, I have
> changed to
> "md5".  When I change back to "peer" the error messages go away.  The
> processes are
> too short-lived for me to catch with ps.  Successful connect message
> example:
>
>   2018-05-21 23:25:13.577 MDT [21080][[unknown]] [unknown](at)[unknown]
> LOG:  connection received: host=[local]
>   2018-05-21 23:25:13.578 MDT [21080][[unknown]] postgres(at)postgres
> LOG:  connection authorized: user=postgres database=postgres
>   2018-05-21 23:25:13.579 MDT [21080][psql] postgres(at)postgres LOG:
> disconnection: session time: 0:00:00.002 user=postgres database=postgres
> host=[local]
>
> My question is, how can I find out where the connections are coming from
> so I can
> modify them to provide passwords (so I can go back to "md5")?  Are there

From the error messages it looks like your connections are already
supplying passwords. I am guessing that the issue is that you have not
created a password for the database user postgres. See the below:

https://help.ubuntu.com/community/PostgreSQL

Basic Server Setup

for how to do that. If you have set up a password then the connections
are using the wrong one. For catching the connections uncomment and set
to on:

log_connections
log_disconnections

in postgresql.conf.

You might also try something like:

watch -n 0.5 'ps aux|grep post'

to see if you catch the connections from the system end.

> startup-
> time connections made by postgresql itself or is this likely from some
> Ubuntu-
> specific configuration?
>
> Thanks.
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com