How to change a password for PostgreSQL on Linux via Command line?

Since PostgreSQL is recognized for supporting a wide range of client authentication techniques, we will just be concerned with two in this instance: password and md5.

Prerequisites:

1) The instruction is specially used for changing a password in PostgreSQL.

2) The instructions are performed by using a Hostvento Core Managed CentOS 7 server and we are logged in a root.

3) PostgreSQL is already installed.

Step 1: Switch to the PostgreSQL user: postgres

N case you are working from a default PostgreSQL installation, then PostgreSQL will be configured with the user postgres.

As we are logged in as root, it can be assumed that root doesn’t have a user for PostgreSQL, switch to the default PostgreSQL user: postgres

su - postgres

Now, attempt to connect to PostgreSQL :

psql

At the prompt, enter your password

Password:

The correct and valid response will be similar to :

psql (9.3.9)
Type "help" for help.

postgres=#

Step 2: Add and Change the password for the PostgreSQL user: postgres

Using the following command you can change the password for your current user, which is now postgres :

\password

Enter your new password. Re-enter it to confirm.

Enter new password:
Enter it again:

Now quit the PostgreSQL interface using the following command :

\q

Tip :

You can perform all the above-mentioned steps in only one command :

su -c "psql" - postgres

That’s it.