This is normal and expected behavior. The appliance is on a secured subnet. Trying to ping the appliance will always fail due to secure firewall built into the appliance.
There is a section in the Installation & Administration Guide on page 91: "About the Security of Your FxM Appliance". And then there is the section: "FEM's Security Layers: FEM employs multiple layers of defense to protect itself against intrusion detection systems". Its Layer 3 is Customized Fedora OS Distribution in which access for potentially exploitable tools needed by FEM (such as ping and traceroute) has been severely restricted. FEM does require the ping tool in order to verify network access during the installation process. This is only available through the Console Setup Program, whose access requires a different account than that used to access the FEM Web Console.