After upgrading Ubuntu, many users encounter this puzzling error where Apache complains about a missing httpd.conf file - a file that was never part of the default Debian/Ubuntu Apache installation in the first place. Let's dive into why this happens and how to fix it.

Ubuntu/Debian's Apache packaging uses a modular configuration system that's different from the traditional httpd.conf approach. Your directory listing shows the standard structure:

conf.d/
mods-available/
mods-enabled/
sites-available/
sites-enabled/
apache2.conf
envvars
ports.conf

The key players here are apache2.conf (main config) and the Include directives that pull in other files.

During upgrades, sometimes old configuration directives get carried forward. Check line 215 of your apache2.conf (as indicated in the error) - you'll likely find something like:

# OBSOLETE: Remove this after upgrade
Include /etc/apache2/httpd.conf

This line needs to be removed or commented out.

Modern Ubuntu Apache configurations should use the following include structure instead:

# These are the correct includes for Debian/Ubuntu
IncludeOptional conf-enabled/*.conf
IncludeOptional sites-enabled/*.conf
IncludeOptional mods-enabled/*.load
IncludeOptional mods-enabled/*.conf

After making changes, always verify your configuration:

sudo apache2ctl configtest
sudo systemctl restart apache2

Check the status with:

systemctl status apache2.service

If you have legacy configurations that need preservation, you can:

sudo touch /etc/apache2/httpd.conf
sudo chmod 644 /etc/apache2/httpd.conf

Then move your custom configurations into this file.

Remember that Ubuntu uses sites-available and sites-enabled for virtual hosts. Example virtual host:

<VirtualHost *:80>
    ServerName example.com
    DocumentRoot /var/www/html
    <Directory /var/www/html>
        Options Indexes FollowSymLinks
        AllowOverride All
        Require all granted
    </Directory>
</VirtualHost>

Enable it with:

sudo a2ensite example.com.conf

Always check logs when troubleshooting:

sudo tail -f /var/log/apache2/error.log

This often reveals more specific issues than the generic configtest failure.

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After an Ubuntu upgrade, many Apache users encounter this configuration error because the package maintainers have changed the default configuration structure. Modern Ubuntu versions use a modular approach where configurations are split across multiple files in /etc/apache2.

# Typical modern Apache2 directory structure:
/etc/apache2/
├── apache2.conf          # Main configuration
├── conf-available/       # Available configuration snippets
├── conf-enabled/         # Enabled configuration snippets
├── mods-available/       # Available modules
├── mods-enabled/         # Enabled modules
├── sites-available/      # Available site configurations
├── sites-enabled/        # Enabled site configurations
├── ports.conf            # Ports configuration
└── envvars               # Environment variables

The error occurs because your apache2.conf still contains this legacy line:

# This is line 215 causing the error
Include /etc/apache2/httpd.conf

Modern Ubuntu versions no longer use httpd.conf as the primary configuration file. The functionality has been distributed across various files in the new structure.

Option 1: Remove the obsolete include (recommended)

sudo sed -i '/Include \/etc\/apache2\/httpd.conf/d' /etc/apache2/apache2.conf
sudo systemctl restart apache2

Option 2: Create an empty httpd.conf file (temporary fix)

sudo touch /etc/apache2/httpd.conf
sudo systemctl restart apache2

After making changes, always test your configuration:

sudo apache2ctl configtest
# Expected output: Syntax OK

sudo systemctl status apache2
# Should show active (running)

For the modern Apache2 structure on Ubuntu:

• Place virtual host configurations in /etc/apache2/sites-available/
• Enable them with a2ensite command
• Add module configurations in /etc/apache2/mods-available/
• Use a2enmod to enable modules

If problems persist, check these logs:

# View error log in real-time
sudo tail -f /var/log/apache2/error.log

# Check for failed services
sudo systemctl --failed

Remember that after major Ubuntu upgrades, it's often necessary to review and update configuration files as default locations and structures may change.