Europa Spam Filter and Email Server Deployment Configuration
The standard deployment configuration consists of a single Europa Appliance with the Email Service turned on. Simply connect the Europa Appliance to your network by assigning it a new IP address and changing your MX record to point to the Europa Appliance.

Europa Spam Filter and Fail-over Redundant Email Server Deployment Configuration
The Fail-over Redundant Email Server deployment configuration consists of a single Europa Appliance similar to the first configuration. When the Email Server is down, Europa can automatically (or manually) become the Email Server. An alert message will be sent to a list of configured notify users.  When the external Email server is back online, simply turn off the Europa Email service and export the emails back to the external Email server.