PostgreSQL

An open-source object-relational database management system.

Install

Install on Fedora

Config

Config file can be found with:

sudo find / -iname "pg_hba.conf" -print

It’s default location should be /var/lib/pgsql/data/pg_hba.conf

This file controls:

• which hosts are allowed to connect
• how clients are authenticated
• which PostgreSQL user names they can use
• which databases they can access.

Example records forms:

local         DATABASE  USER  METHOD  [OPTIONS]
host          DATABASE  USER  ADDRESS  METHOD  [OPTIONS]
hostssl       DATABASE  USER  ADDRESS  METHOD  [OPTIONS]
hostnossl     DATABASE  USER  ADDRESS  METHOD  [OPTIONS]
hostgssenc    DATABASE  USER  ADDRESS  METHOD  [OPTIONS]
hostnogssenc  DATABASE  USER  ADDRESS  METHOD  [OPTIONS]

First field is the connection type:

• local - Unix-domain socket
• host - TCP/IP socket (encrypted/not encrypted)
• hostssl - TCP/IP socket that is SSL-encrypted
• hostnossl - TCP/IP socket, not SSL encrypted
• hostgssenc - TCP/IP socket, GSSAPI-encrypted
• hostnogssenc - TCP/IP socket, not GSSAPI-encrypted

DATABASE can be:

• all (does not match replication)
• sameuser
• samerole
• replication
• a database names
• comma separated list of values above

USER can be:

• all
• user name
• group name prefixed with +
• comma separated list of values above

To include names from a separate file use @file_name prefix.

ADDRESS specifies the set of hosts the record matches. It can be:

• host name
• IP address in a CIDR notation

METHOD can be:

• trust
• reject
• md5 - encrypted password
• password - in clear text, non-preferable
• scram-sha-256 - encrypted password
• gss
• sspi
• ident
• peer
• pam
• ldap
• radius
• cert

Database and user names with special symbols must be quoted.

Configuration is read of server startup and when SIGHUP signal received (pg_ctl reload, SELECT pg_reload_conf()).

Fix pgadmin ident authentication failed for user

https://www.cyberciti.biz/faq/psql-fatal-ident-authentication-failed-for-user/