Your Website Is Down with a “421 Misdirected Request” Error. Here’s Why.

Woke up this morning to find your website suddenly offline? If you’re seeing a “421 Misdirected Request” error, you’re in the right place. This issue is affecting a huge number of servers globally, typically those using Nginx as a reverse proxy in front of Apache—a very common setup for Plesk on Ubuntu 22.04.

The problem isn’t your fault. It was triggered by a recent security update to Apache that changed how it handles SSL/TLS connections. Don’t worry, this guide provides three clear methods to fix the error and get your site back online immediately.

What is the “421 Misdirected Request” Error?

In simple terms, this error is an SSL handshake failure. Your user’s browser tries to connect securely to your website via Nginx. Nginx then tries to pass this connection to the Apache backend.

However, due to the recent Apache update (version 2.4.58-1ubuntu8.6), Apache now has stricter security rules. It demands to know the exact hostname of the site it’s serving via a technology called SNI (Server Name Indication). Because Nginx wasn’t forwarding this specific piece of information, Apache rejects the connection, resulting in the “421” error.

The fix is to tell Nginx to correctly pass this SNI information to Apache.

Method 2: The One-Line Command (Fastest for CLI Users)

 

This method is for experienced users who are comfortable on the command line and want the quickest possible fix.

1. Connect to your server via SSH.
2. Execute the following single command. It will create the necessary file and restart Nginx in one step.

   echo -e "proxy_ssl_server_name on;\nproxy_ssl_name \$host;" > /etc/nginx/conf.d/fixssl.conf && service nginx restart
   

3. After the command completes, your sites should be back online.

Method 3: Manual File Creation (The Cautious CLI Approach)

 

This method achieves the same result as Method 2, but allows you to manually create and edit the file, which some users prefer.

1. Connect to your server via SSH.
2. Open a new configuration file using a text editor like nano:

   sudo nano /etc/nginx/conf.d/fixssl.conf
   

3. Paste the following two lines into the empty file:

   proxy_ssl_server_name on;
   proxy_ssl_name $host;
   

4. Save the file and exit the editor by pressing Ctrl+X, then Y, then Enter.
5. Finally, test your Nginx configuration to ensure there are no errors, then restart the service:

   sudo nginx -t && sudo systemctl restart nginx
   

6. If the test is successful, Nginx will restart, and your sites will be back online.

How Black Sheep Support Can Help

Solving complex technical problems like this is a crucial part of managing a digital presence, but it’s just one piece of the puzzle. At Black Sheep Support, we partner with businesses to ensure their entire digital strategy is robust, secure, and aligned with their long-term goals.

While you’re handling the immediate technical fixes, we focus on the bigger picture:

• Strategic Technology Consulting: We help you navigate the complex digital landscape, ensuring you have the right technology and processes in place for sustainable growth.

• Proactive Risk Management: We help you identify potential technical and security vulnerabilities across your digital ecosystem before they become critical problems.

• Process & Policy Development: We assist in creating clear internal policies that empower your team to use technology safely and effectively.

• Data Security & Compliance: We provide guidance on ensuring your data handling practices are secure and compliant, minimising business risk.

To get started, we offer a free consultation where we’ll review your current setup and tailor a strategy that balances strong security with effective AI use.

Contact Black Sheep Support today to protect your sensitive information and confidently harness the power of AI—without the fear of accidental data leaks.