Software⏱️ 3 min read📅 2026-06-04

How to Fix: connect() failed (111: Connection refused) while connecting to upstream

Nginx configuration issue causing Connection refused error.

Quick Answer: Check if the PHP-FPM service is running and configured correctly, as the upstream server is trying to connect to 127.0.0.1:9000.

📋 Table of Contents

  1. 🛑 Root Causes of the Error
  2. 🛠️ Step-by-Step Verified Fixes
  3. ✨ Wrapping Up

The error 'connect() failed (111: Connection refused) while connecting to upstream' occurs when the PHP script is unable to establish a connection with the FastCGI server, resulting in a 502 Gateway error. This issue affects servers running Nginx and PHP, particularly those using the fastcgi module.

This error can be frustrating for developers as it prevents them from accessing their PHP files, causing delays in development and deployment. In this guide, we will walk you through the root causes of this error and provide two methods to resolve it.

🛑 Root Causes of the Error

  • The primary reason for this error is that the FastCGI server is not running or not listening on the specified port (in this case, 9000). This can be due to a misconfiguration in the Nginx configuration file or an issue with the FastCGI module.
  • An alternative reason could be that the PHP script is trying to connect to a non-existent FastCGI server or the connection timeout has been set too low.

🛠️ Step-by-Step Verified Fixes

Enabling and Configuring FastCGI

  1. Step 1: Enable the fastcgi module in Nginx by adding the following line to the nginx.conf file: "fastcgi_pass 127.0.0.1:9000;"
  2. Step 2: Restart the Nginx service to apply the changes: "sudo service nginx restart" or "sudo systemctl restart nginx" depending on your system.
  3. Step 3: Verify that the FastCGI server is running by checking the process list: "ps aux | grep php-fpm"
  4. Step 4: Check the Nginx configuration file for any typos or incorrect port numbers.

Increasing Connection Timeout

  1. Step 1: Add the following line to the nginx.conf file under the fastcgi_pass directive: "fastcgi_read_timeout 30s;"
  2. Step 2: Restart the Nginx service to apply the changes: "sudo service nginx restart" or "sudo systemctl restart nginx" depending on your system.
  3. Step 3: Verify that the connection timeout has been increased by checking the process list: "ps aux | grep php-fpm". If the process is still exiting, proceed with enabling and configuring FastCGI.

✨ Wrapping Up

To resolve the 'connect() failed (111: Connection refused) while connecting to upstream' error in Nginx and PHP, you can either enable and configure the FastCGI module or increase the connection timeout. By following these steps, you should be able to establish a successful connection with your FastCGI server and access your PHP files without any issues.

Did this fix your problem?

If not, try searching for specific error codes.

🔍 Search Error Database

❓ Frequently Asked Questions

🛠️ Related Fixes

How to Fix: Pc crashes shortly after launching game (rainbow

Fix Pc crashes shortly after launching game (rainbow six siege). Compl

How to Fix: Installing an APK on a locked down phone

Installing an APK on a locked down phone: Try using a rooted device, e

How to Fix: New PC build- no signal and no clue

Fix New PC build- no signal and no clue. Complete troubleshooting guid