NGINX Error 405: Method Not Allowed: Solutions Guide

Introduction

Encountering a ‘405 Method Not Allowed’ error can be frustrating for both users and web developers. This error occurs when the web server is configured to reject specific types of HTTP methods for a requested resource. In NGINX, fixing this error involves server configuration adjustments and a clear understanding of the permitted HTTP methods.

Understanding The Error

HTTP methods such as GET, POST, PUT, DELETE, and others are used by clients to communicate with a web server. When NGINX returns a 405 error, it implies that the server received an HTTP request with a method that is not supported or not allowed for the requested resource. Common causes include inappropriate request handling configuration, missing server directive, or incorrect location blocks.

Solution 1: Allow Specific HTTP Methods

The most straightforward solution is to ensure NGINX allows the required HTTP methods. By default, NGINX permits GET and HEAD methods. Other methods like POST, PUT, DELETE might not be allowed by default and would require explicit configuration.

• Identify the location block in NGINX configuration file where the method should be allowed.
• Use the limit_except directive to specify allowed methods.
• Restart NGINX to apply the changes.

server {
    location / {
        limit_except GET POST {
            deny all;
        }
        ...
    }
}

This method securely opens up endpoints for certain HTTP methods while blocking others. It is essential to only allow necessary methods to minimize security risks, such as unauthorized data alteration.

Solution 2: Configuring Correct Error Pages

If you want to provide users with a custom error page instead of the default NGINX message when a method is not allowed, you can configure a specific error page.

• Open the NGINX configuration file for editing.
• Set up a custom error page directive within the server block.
• Ensure that the file specified in the directive exists on the server.
• Reload or restart NGINX to see the change.

server {
    ...
    error_page 405 = /custom_405.html;
    location = /custom_405.html {
        root /usr/share/nginx/html;
        internal;
    }
    ...
}

This solution enhances the user experience by showing more user-friendly error messages. Make sure the custom error pages are helpful and guide the user to possible next steps.

Solution 3: Verify API Endpoint Configuration

Sometimes, a mismatch or typo in the API endpoint configuration can cause the 405 error. Verify that the server block or location directive points to the correct handler for the required HTTP method.

• Check if the script referred to in the fastcgi_pass, proxy_pass, or similar directives, supports the HTTP method that is failing.
• Ensure there are no typos in the URL patterns, location block, or directive values.
• Reload or restart NGINX after making any changes.

The solution will vary based on the configuration and the backend setup. Review the scripts or application configuration to support the HTTP method used.

This is a more complex solution and requires understanding of the application architecture and proper debugging. Incorrect configurations here can lead to security issues or application malfunctions.

Conclusion

The ‘NGINX Error 405: Method Not Allowed’ message is a common issue that can be addressed by reviewing and adjusting server configurations. By understanding the HTTP methods workflow and careful NGINX configuration, the 405 error can generally be resolved with little downtime.