Resolving the “could not connect to server” Error in PostgreSQL

Introduction

Encountering the “could not connect to server” error in PostgreSQL can be a frustrating experience, especially when you’re in the middle of a critical task. This error typically indicates an issue with the connection between your client and the PostgreSQL server. In this article, we will explore various methods to diagnose and resolve this common problem.

Check PostgreSQL Server Status

First, ensure that the PostgreSQL server is running. You can check the status of the PostgreSQL service using the following command:

sudo service postgresql status

If the server is not running, start it with:

sudo service postgresql start

Verify Connection Settings

Incorrect connection settings can also cause this error. Double-check your connection parameters such as host, port, username, and password. Ensure that the host and port you’re trying to connect to are correct:

• Host: Ensure that the hostname is correct and that you’re not using an incorrect IP address.
• Port: PostgreSQL uses port 5432 by default. Verify that the correct port number is specified.
• Username and Password: Confirm that the provided credentials are accurate.

Firewall and Network Configuration