PGBouncer : Cant connect on the right db - postgresql

Question

I'm actually facing an issue. I've installed pgbouncer on a production server, on which i've a Odoo instance and postgresql as well.
Perhaps :
In my logs, i'm having this :
2018-09-10 16:39:16.389 10123 WARNING C-0x1eb5478:
(nodb)/(nouser)#unix(18272):6432 pooler error: no such database: postgres
2018-09-10 16:39:16.389 10123 LOG C-0x1eb5478: (nodb)/(nouser)#unix(18272):6432 login failed: db=postgres user=oerppreprod
Here is the actual conf of pgbouncer :
pgbouncer_archive = host=127.0.0.1 port=5432 dbname=archive
admin_users = postgres
ignore_startup_parameters = extra_float_digits
With aswell, the default config (i've only added/edited this).
Why is he trying to connect on the postgres database ?
When i go back on the previous conf (without PGBouncer, just swapping from port 6432 to 5432), everything is working ....
Any idea ?
Thanks in advance !

Answer 1

I had the same issue, and in my situation. Maybe it will be usefull to somebody:
I have solved this by a few steps:
At the beginning of every request - your Framework or PDO (or else) running the initial query to check if database you asking is exists in the postgres data to process you request.
I have replaced the part of line "user=project_user password=mytestpassword" from the database section of pgbouncer.ini file. As I tested, if you replace this part - then the pgbouncer will use your userlist.txt file (or your selected auth), in my case, it was the userlist.txt.
Added the line "postgres = host=127.0.0.1 port=5432 dbname=postgres"
[databases]
postgres = host=127.0.0.1 port=5432 dbname=postgres
my_database = host=127.0.0.1 port=5432 dbname=my_database
My userlist.txt file looks like this (I am using auth_type = md5, so my password was in md5):
"my_user" "md5passwordandsoelse"
I have added my admin users to my pgbouncer.ini file:
admin_users = postgres, my_user
After all manipulations I advise you to check from which user u are running queries, by usin this simple query:
select current_user;
At the end, with this query you must to receive you selected username (in my case it was - my_user)
p.s. also I must to mention, that I was using 127.0.0.1 - because my pgbouncer is installed on the same server with postgres.