When working with Apache 2.2, there are several scenarios where you might want to route all incoming requests to a single entry point (typically index.html). This is particularly common in:

• Single Page Applications (SPAs)
• Maintenance mode setups
• Legacy system migrations

The original approach using Redirect 302 has limitations because:

# This won't work as expected:
Redirect 302 !^/index.html http://www.example.com/index.html

The Redirect directive doesn't handle complex pattern matching well. What you actually need is mod_rewrite functionality.

Here's the correct implementation for your .htaccess file:

RewriteEngine On
RewriteCond %{REQUEST_URI} !^/index\.html$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^ /index.html [L]

This solution works because:

1. RewriteCond %{REQUEST_URI} !^/index\.html$ ensures we don't create infinite loops
2. The !-f and !-d conditions prevent rewriting real files/directories
3. The [L] flag makes this the last rule to process

For server config files (more efficient than .htaccess):

<VirtualHost *:80>
    ServerName example.com
    DocumentRoot /var/www/html
    
    RewriteEngine On
    RewriteRule ^/(?!index\.html$).* /index.html [PT]
</VirtualHost>

For SPAs that need the original path available to JavaScript:

RewriteEngine On
RewriteCond %{REQUEST_URI} !^/index\.html$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^ /index.html [L,QSA]

The QSA flag keeps query strings intact.

Remember that rewrite rules execute for every request. For high-traffic sites:

• Place rules in main config rather than .htaccess
• Minimize the number of conditions
• Consider using fallback resources in newer Apache versions

If rewrites aren't working:

1. Verify mod_rewrite is enabled (a2enmod rewrite)
2. Check Apache error logs
3. Ensure AllowOverride All is set for .htaccess files
4. Test with RewriteLog directives for debugging

For Apache 2.4+, consider:

FallbackResource /index.html

This single directive handles all missing file cases more efficiently.

Many developers mistakenly use Redirect when they actually need RewriteRule in Apache. The key differences:

Redirect: Sends HTTP 302/301 response to client, changing URL in browser address bar
RewriteRule: Internally maps requests without changing visible URL



For modern SPAs that handle routing client-side, use this in your .htaccess:
RewriteEngine On
RewriteBase /

# Skip actual files and directories
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

# Rewrite everything else to index.html
RewriteRule ^(.*)$ index.html [L]

For API requests or static files that should bypass the rewrite:
RewriteCond %{REQUEST_URI} !^/api/
RewriteCond %{REQUEST_URI} !\.(css|js|png|jpg)$
RewriteRule ^(.*)$ index.html [L]

If you're stuck on Apache 2.2, ensure these modules are loaded:
LoadModule rewrite_module modules/mod_rewrite.so
LoadModule alias_module modules/mod_alias.so

Add this to your vhost config to debug rewrite issues:
LogLevel alert rewrite:trace6
RewriteLog "/var/log/apache2/rewrite.log"
RewriteLogLevel 3

For high-traffic sites, cache the rewritten routes:
<IfModule mod_cache.c>
    CacheEnable disk /
    CacheHeader on
</IfModule>