How to Fix Apache 2.4 Broken Directory Requests

Introduction

I’m currently re-architecting my non-profit accounting SaaS (Treasurer’s Briefcase) to use Docker containers for a portable development environment and eventually for running under Kubernetes. The current architecture designed in 2012 uses an EC2 based environment for both development and run-time execution.

As part of that effort I’m migrating from Apache 2.2 to 2.4. In the new development environment I’m using my Chromebook to access the containerized application running on the EC2 dev server. I described that setup in my previous blog. In that setup I’m accessing the application on port 8080 as http://local-dev:8080.

If, as in the setup describe in my blog, you are running Apache on a non-standard port (e.g., :8080) - perhaps in Docker, EC2, or via an SSH tunnel you may have noticed an annoying issue after migrating from Apache 2.2 to Apache 2.4…

Apache 2.4 Drops the Port When Redirecting Directories!

Previously, when requesting a directory without a trailing slash (e.g., /setup), Apache automatically redirected to /setup/ while preserving the port. However, in Apache 2.4, the redirect is done externally AND drops the port, breaking relative URLs and form submissions.

For example let’s suppose you have a form under the /setup directory that has as its action “next-step.html”. The expected behavior on that page would be to post to the page /setup/next-step.html. But what really happens is different. You can’t even get to the form in the first place with the URL http://local-dev:8080/setup!

• Expected Redirect (Apache 2.2):\ http://yourserver:8080/setup => http://yourserver:8080/setup/
• Actual Redirect (Apache 2.4, Broken):\ http://yourserver:8080/setup => http://yourserver/setup/ (port 8080 is missing!)

This causes problems for some pages in web applications running behind Docker, SSH tunnels, and EC2 environments, where port forwarding is typically used.

Investigating the Issue

If you’re experiencing this problem, you can confirm it by running:

curl -IL http://yourserver:8080/setup

You’ll likely see:

HTTP/1.1 301 Moved Permanently
Location: http://yourserver/setup/

Apache dropped 8080 from the redirect, causing requests to break.

Workarounds

Several workarounds exist, but they don’t work in our example.

• Disabling DirectorySlash: Prevents redirects but causes 403 Forbidden errors when accessing directories.
• Using FallbackResource: Works, but misroutes unrelated requests.
• Hardcoding the port in rewrite rules: Not flexible across different environments.

Instead, we need a solution that dynamically preserves the port when necessary.

The Fix

To restore Apache 2.2 behavior, we can use a rewrite rule that only preserves the port if it was in the original request.

Apache 2.4 Fix: Port-Preserving Rewrite Rule

<VirtualHost *:8080>
    ServerName yourserver
    DocumentRoot /var/www/html

    <Directory /var/www/html>
        Options -Indexes +FollowSymLinks
        DirectoryIndex index.html index.php
        Require all granted
        DirectorySlash On  # Keep normal Apache directory behavior
    </Directory>

    # Fix Apache 2.4 Directory Redirects: Preserve Non-Standard Ports
    RewriteEngine On
    RewriteCond %{REQUEST_URI} !/$
    RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_URI} -d
    RewriteCond %{SERVER_PORT} !^80$ [OR]
    RewriteCond %{SERVER_PORT} !^443$
    RewriteRule ^(.*)$ http://%{HTTP_HOST}/$1/ [R=301,L]

    UseCanonicalName Off
</VirtualHost>

Explanation

• Automatically appends a missing trailing slash (/setup => /setup/).
• Preserves the port only if it’s non-standard (!=80, !=443)
• Avoids hardcoding :8080, making it flexible for any non-standard port
• Restores Apache 2.2 behavior while keeping things modern and correct.

Example: Running Apache in Docker on EC2 via SSH Tunnel

The Setup (see previous blog)

1. Docker container running Apache on port 80 inside an EC2 instance.
2. Firewall rules allow only my home IP to access the server.
3. SSH tunnel (jump box) forwards port 80 securely.
4. Chromebook’s SSH settings forward port 8080 locally to 80 on the jump box.

How the Fix Helps

• Previously, /setup redirected externally without the port, causing failures.
• This fix use mod_rewrite and a RewriteRule that ensures that port 8080 is preserved

Conclusion

Apache 2.4’s port-dropping behavior is an unexpected regression from 2.2, but we can fix it with a simple rewrite rule that restores the expected behavior without breaking anything.

If you’re running Docker, EC2, or SSH tunnels, this is a fix that will prevent you from jumping through hoops by altering the application or changing your networking setup.

Postamble

Hmmmm…maybe we can use internal redirects instead of an external redirect??? Stay tuned.