Adding Cache Settings for JavaScript Files to Improve NPS Page Load Performance

Overview

This article describes how to create an IIS configuration setting that updates the Cache-Control header for all JavaScript files that are downloaded from the Netwrix Privilege Secure for Access Management web service. This setting improves the performance of the website and lowers the burden on the webservice.

The main ReactJS bundle for the Privilege Secure website is 6.5MB. This is sent with the HTTP header Cache-Control: no-cache, no-store. This causes SAML Logins to sometimes fail, as downloading the ReactJS module during each login can cause the SAML token cache to expire.

Instructions

1. On all Privilege Secure servers, download and install the Url Rewrite module.

   https://www.iis.net/downloads/microsoft/url-rewrite

2. Go to your Privilege Secure Web directory (by default, C:\Program Files\Stealthbits\PAM\Web\) and make a copy of the web.config file.

3. Open the file C:\Program Files\Stealthbits\PAM\Web\web.config in a text editor. Find this line:

   <system.webServer>

4. Add the following XML after that line:

   <rewrite>
     <outboundRules>
       <rule name="Set cache for JS">
         <match serverVariable="RESPONSE_Cache_Control" pattern=".*" />
         <conditions>
           <add input="{REQUEST_URI}" pattern="\.js$" />
         </conditions>
         <action type="Rewrite" value="max-age=604800"/>
       </rule>
     </outboundRules>
   </rewrite>

5. Save the file.

6. Launch a PowerShell window and restart IIS using the command:

   iisreset

7. To verify the file is now cached, open Chrome or Edge and then open the developer tools.

8. Open your Privilege Secure web page and look at the Network tab in the developer tools window.

9. See the page download:

   

10. Reload the page, see it is loaded from the cache:

    

11. Copy the updated web.config to C:\Program Files\Stealthbits\PAM\Web\web.config.rewrite; you need this copy for future upgrades.

Restoring the Cache Settings After an Upgrade

After an upgrade of Privilege Secure, copy the C:\Program Files\Stealthbits\PAM\Web\web.config.rewrite file to C:\Program Files\Stealthbits\PAM\Web\web.config to restore the cache settings.