Implementing server-side caching on IIS 10 improves performance by reducing the load on the web server and serving cached content to users. Here’s a step-by-step guide to enable server-side caching on IIS 10:

1. Enable Output Caching

Output caching stores dynamic content responses to serve repeated requests faster.

Step 1: Install Output Caching Feature

1. Open Server Manager.
2. Go to Manage > Add Roles and Features.
3. In the Add Roles and Features Wizard, select Web Server (IIS) > Performance.
4. Check Output Caching and install it.

Step 2: Configure Output Caching in IIS Manager

1. Open IIS Manager.
2. Select your site in the Connections panel.
3. In the Features View, double-click Output Caching.
4. Click “Add” in the right-hand panel to define caching rules:
   • File extensions: Define specific extensions to cache (e.g., .html, .aspx).
   • Cache-Control header: Choose whether to bypass caching when no-cache headers exist.
   • Vary by parameters: Cache different versions based on query string parameters.
5. Click Apply to save the settings.

2. Enable Kernel Caching (Static Content)

Kernel caching speeds up requests for static content like images, CSS, and JavaScript.

Enable Kernel Caching in IIS Manager

1. In IIS Manager, select your site.
2. Open Output Caching.
3. Check Enable cache and Enable kernel cache.
4. Apply changes.

3. Configure HTTP Response Caching

To leverage browser and proxy caching, configure HTTP headers.

Modify HTTP Response Headers

1. In IIS Manager, select your site.
2. Open HTTP Response Headers.
3. Click Set Common Headers and configure:
   • Expire Web Content: Set expiration time for static files.
   • Enable ETag headers: Helps cache validation.
4. Click Apply.

4. Configure Disk-based Caching (Output Cache Module)

This allows IIS to store cached responses on disk instead of memory.

Enable Disk Cache via Configuration

Modify applicationHost.config or web.config:

<system.webServer>
    <caching>
        <profiles>
            <add extension=".aspx" policy="CacheUntilChange" location="ClientAndServer" />
            <add extension=".html" policy="CacheUntilChange" location="ClientAndServer" />
        </profiles>
    </caching>
</system.webServer>

Policies:

• CacheUntilChange: Caches content until the file changes.
• CacheForTimePeriod: Defines a custom time-based cache.
• DontCache: Disables caching.

5. Enable Application Request Routing (ARR) Cache

For reverse proxy caching, use ARR.

Install and Enable ARR Cache

1. Install Application Request Routing (ARR) via Web Platform Installer.
2. Open IIS Manager > Server Node.
3. Go to Application Request Routing Cache.
4. Click Server Proxy Settings and enable Response Caching.

6. Use IIS Compression for Additional Performance Boost

Enable Dynamic and Static Compression for faster content delivery.

1. In IIS Manager, select your site.
2. Open Compression.
3. Enable static compression (CSS, JS, images).
4. Enable dynamic compression (ASP.NET pages).
5. Click Apply.

Verification

• Use Developer Tools (F12) > Network to check cache behavior.
• Run iisreset to apply settings.

This setup significantly reduces server load, improves speed, and enhances scalability. Let me know if you need help with a specific configuration! 🚀