PostgreSQL Remote Connection Configuration Management/account password Assignment (FIX: Fatal error: User "Postgres" Ident authentication failed)

Problem: Fatal error: User "Postgres" Ident authentication failed

Note: This is because there is no remote access configured and authentication method has not changed, only need to change the use of account password authentication.

Workaround: Locate pg_hba.conf (Find/-name pg_hba.conf), change the ident of method to MD5, and change the IP port to 0.0.0.0/0, or the desired IP address. After the modification is completed, the direct reload can be.

Special Spit Groove: Online said direct trust, in fact, this means only to verify the user name, do not verify the password! Never use this!!!

METHOD specifies how the client's authentication is handled. Commonly used are ident,md5,password,trust,reject.

Ident is the default local authentication method under the Linux PostgreSQL, the user who can log on to the server correctly (note: not a database user) can use this user mapping database users do not need a password to log in to the database. The user mapping file is pg_ident.conf, which records database users that match the operating system user, and if an operating system user does not have a mapped user in this file, the default mapping database user has the same name as the operating system user. For example, the server is known as User1 operating system users, and the database also has the same name of the database user, User1 log on to the operating system can be directly entered Psql, to User1 database users to log into the database and do not require a password. Many beginners will encounter psql-u username login database But "Username ident authentication failed" error, clearly the database user has createuser. The reason for this is that the Ident authentication method is used, but there is no operating system user with the same name or no corresponding mapping user. Solution: 1, add the mapping user in pg_ident.conf, 2, change the authentication method.

MD5 is a common method of password authentication, if you do not use ident, it is best to use MD5. The password is transmitted to the database in the form of MD5, which is more secure and does not require an operating system user with the same name.

Password is sent to the database in plaintext and is not recommended for use in a production environment.

Trust does not require a password or ident to log in as long as the database username is known, and is not recommended for use in a production environment.

Reject is a denial of certification.

In the file lookup listen_addresses, his value description

If you want the PostgreSQL database to be accessible only from the local computer, set the entry to ' localhost ';
If you want to access the PostgreSQL database from the LAN, set the key to the LAN IP address of the PostgreSQL database;
If you want to access the PostgreSQL database from the Internet, set this to the Internet IP address of the PostgreSQL database;
If you want to access the PostgreSQL database from anywhere, set the configuration item to "*";

To create a user:

# Create database user dbuser first
Postgres=# create user dbuser with password ‘password’;
# Create system user
Adduser dbuser
# Modify system user password
Passwd dbuser

To modify the Dbuser password:

# Switch user to Postgresu postgres# Login psql# Modify dbuser password postgres=# alter user Dbuser with password ' own password ';
# or
postgres=# \password Dbuser

Assigning database permissions to Dbuser:

# Assign when creating a database
Postgres=# create database database name owner dbuser;
# Give the user postgres permission after creating the database
Postgres=# grant all privileges on database database name to dbuser;

Connect to the database as Dbuser:

Su dbuserpsql-d database name

Reference:

46047483

Http://www.ruanyifeng.com/blog/2013/12/getting_started_with_postgresql.html

PostgreSQL Remote Connection Configuration Management/account password Assignment (FIX: Fatal error: User "Postgres" Ident authentication failed)