This is the default example configuration of user_map.conf provided by MariaDB. This config file was generated by MariaDB running on CentOS 8.
It is located under: /etc/security/user_map.conf
#
# Configuration file for pam_user_map.so
#
# defines mapping in the form
#
# orig_user_name: mapped_user_name
#
# or (to map all users in a specific group)
#
# @group_name: mapped_user_name
#
# comments and empty lines are ignored
#
Download the raw file with wget or curl
wget -O user_map.conf.example http://exampleconfig.com/static/raw/mariadb/centos8/etc/security/user_map.conf
curl http://exampleconfig.com/static/raw/mariadb/centos8/etc/security/user_map.conf > user_map.conf.example
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