Verify the following:
Using the JRE installer, you can configure your browser for Java Web Start. Also, ensure that you have configured your browser to open .jnlp files using the Java Web Start application or javaws exe located in the bin folder of your JRE installation.
When you access the Gluster Management Console, Java Web Start downloads all required .jar files from the gateway server and launches the console’s GUI. During this process, web start may display a certificate warning mentioning that the application is signed by Gluster, Inc., which is authentic, but it requires full permissions as the application contains features that require registering information on the client’s hard disk such as exporting the security keys from gateway. You can accept this warning and select Always Trust Content from this Provider on your browser to avoid getting this warning every time you launch the application.