The error message you're encountering (Invalid command 'RewriteLog') occurs because these directives were removed in Apache 2.4+. The logging functionality has been integrated into the core error log using the LogLevel directive instead.

For Apache 2.4+, use this configuration in either your virtual host or .htaccess:

RewriteEngine On
RewriteBase /

# For Apache 2.4+ debugging

LogLevel alert rewrite:trace5


RewriteRule ^/wordpress/wp-content/(.*)$ /wp-content/$1 [L]
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]

The rewrite traces will appear in your main Apache error log (typically /var/log/apache2/error.log). To monitor logs in real-time:

tail -f /var/log/apache2/error.log | grep "rewrite:trace"

Even with correct configuration, you might need to:

sudo chmod 644 /var/log/apache2/error.log
sudo service apache2 restart

If you don't have access to server logs, insert debugging rules:

RewriteRule ^(.*)$ - [E=DEBUG_PATH:%{REQUEST_URI},L]
Header set X-Rewrite-Debug "%{DEBUG_PATH}e" env=DEBUG_PATH

A sample trace entry looks like:

[rewrite:trace3] applying pattern '^index\.php$' to uri 'test.html'
[rewrite:trace4] RewriteCond: input='/var/www/test.html' pattern='!-f' => matched

The error message you're seeing (Invalid command 'RewriteLog') occurs because these directives were removed in Apache 2.4. The traditional debugging approach using RewriteLog and RewriteLogLevel no longer works in current Apache versions. Here's what changed:

# Old Apache 2.2 syntax (deprecated):
RewriteLog "/path/to/logfile"
RewriteLogLevel 3

# Apache 2.4+ replacement:
LogLevel alert rewrite:trace6

For Apache 2.4+, you'll need to configure rewrite logging through the main Apache configuration rather than .htaccess:

# In your Apache config (httpd.conf or virtual host file)
<VirtualHost *:80>
    ServerName example.com
    LogLevel debug
    ErrorLog /var/log/apache2/example_error.log
    CustomLog /var/log/apache2/example_access.log combined
    
    # Specific rewrite logging (levels 1-8, 8 being most verbose)
    LogLevel alert rewrite:trace6
</VirtualHost>

Here's how to properly debug your WordPress rewrite rules:

1. Modify your main Apache config (not .htaccess)
2. Restart Apache: sudo service apache2 restart
3. Make test requests
4. Check error logs: tail -f /var/log/apache2/error.log

When working correctly, you'll see detailed rewrite processing:

[rewrite:trace3] applying pattern '^/wordpress/wp-content/(.*)$' to uri '/wordpress/wp-content/themes/style.css'
[rewrite:trace2] rewrite '/wordpress/wp-content/themes/style.css' -> '/wp-content/themes/style.css'
[rewrite:trace1] internal redirect with /wp-content/themes/style.css [INTERNAL REDIRECT]

If you can't modify server configs, try these alternatives:

# Add environment variable logging
RewriteRule ^ - [E=DEBUG_MSG:%{REQUEST_URI},L]
Header set X-Rewrite-Debug "%{DEBUG_MSG}e" env=DEBUG_MSG

# Or use PHP to log rewrite behavior
<?php
file_put_contents('rewrite_debug.log', $_SERVER['REQUEST_URI']."\n", FILE_APPEND);
?>

Ensure your log directory has proper permissions:

sudo chown www-data:www-data /var/log/apache2/
sudo chmod 755 /var/log/apache2/