Java Applet Usage in the Guest Portal

The Guest Portal uses a Java applet based Web Agent. This is used to collect system health information. Based on this information, appropriate network access is granted to the client system.

Recommendations and Solutions to common problems

Run the latest Java version

Always install the latest Java version available. Download and install the latest version from

Verify that your browser is setup to run applets

Ensure that you have the recommended version of Java and your browser can run Java applets. Confirm that "Enable Java content in the browser" option is enabled in the Java Control Panel (needs browser restart for changes to take effect). Go to the Verify Java version page to confirm this.

Browsers may present popups or warnings asking for explicit permission to run Java applets on this page. This must be permitted for health checks to succeed. A reload of the page may be required for this permission to take effect - reload page and attempt login again.

Do not use Chrome on Mac OSX if health checks are required as a part of login

Chrome on Mac OSX cannot run Java applets. Login using a different browser, like Safari or Firefox, for running health checks as part of login. More details avaialble in the Official FAQ entry.

Safari browser issue: Enable "Unsafe mode" to let applet perform health checks

The applet needs to run in Safari's "Unsafe mode" to perform health checks. This can be enabled in Safari -> Preferences -> Security -> Manage Website Settings -> Java -> [Select IP/hostname of login server] -> Select "Run in Unsafe Mode" in the drop down. Restart Safari for changes to take effect.

Health data collection is not supported in 64-bit Java environments

The health data collection applet only works on 32-bit Java installations. Ensure that you have a 32-bit JRE installed, even if your OS/browser environment is 64-bit. Installing a 64-bit JRE can result in the following issues:

  1. Health data collection fails if you use a 64-bit Java version on a 64-bit browser. The applet will launch but fail to collect health information.
  2. Your browser may be a 32-bit application even though your OS is 64-bit enabled. In such cases, installing a 64-bit Java version does not install the Java browser plugin. The applet will not even launch in such cases.

Firefox on Linux: Applet does not launch

Use instructions in the section Verify that your browser is setup to run applets to verify that your browser is setup to run Java applets. Official instructions for enabling the Java plugin for Firefox are available here

Java Runtime Environment (JRE) Installation

The Web Agent requires JRE 1.6 or above to be installed on your machine. If the required JRE version is not detected on the corresponding browser in use, a notification message prompts the user to install a recent version of Java.

To install JRE 1.7 or above, follow instructions below for your OS.

Installation on Windows

Download the JRE installer.Follow the prompts to install Java Runtime Environment by launching the setup file.

Installation on Mac OSX

Download the JRE installer. Follow the prompts to install Java Runtime Environment by launching the setup file.

Installation on Linux

If you use an RPM based Linux distribution (like RedHat, Fedora, OpenSuSE), you may use RPM based installation method (requires superuser privileges). For other distributions; the binary installer method may be preferable. If you are not sure about which method to use, choose the binary installation method.

RPM-based installation

Download the RPM based installer and launch it with superuser (root) privileges. Depending on your setup, you may have to:

  1. Launch a terminal
  2. Switch to root user:
  3. su root

  4. Now launch the installer:
  5. rpm -Uvh </path/to/installer/file>

  6. Review and accept any license agreement presented and complete Java installation.
  7. This should install Java in the following location:
  8. /usr/java/jre-<version>

Binary installation

  1. Download the binary installer
  2. Launch it from a terminal:
  3. tar zxf </path/to/installer/file>

  4. This should install Java in the current directory. Find the location using pwd in the terminal.


The Web Agent applet does not appear on the page or Java installation is not detected

Verify that a Java Runtime Environment version (1.6 or above) is installed, and the corresponding browser plugin is enabled. Go to the Java Version Test page to verify that your Java installation is working fine.

Viewing Web Agent logs

  1. Enable the Java Console from the Control Panel on Windows or System Preferences on Mac OSX to view logs generated by the applet.
  2. On Linux clients, run </path/to/java/installation>/bin/ControlPanel in a Terminal.
  3. Navigate to the Advanced tab and click on Java Console.
  4. Select Show Console, to view logs generated by the applet.
  5. Restart your browser for changes to take effect.