Bridgehead servers act as the communication relays for routing groups. They are defined both remotelythe destination of email messagesand locallythe source of email messages. Each connector handles bridgehead connectors differently. Routing group connectors can have several local bridgeheads and one remote bridgehead and can be created using the steps described in the section "Configuring Routing Group Connectors" in this lesson. SMTP connectors can have more than one local bridgehead and use smart hosts or DNS MX records to locate remote mail servers. To set up, use the procedures in the section "Configuring SMTP Connectors" in this lesson. X.400 connectors have a one-to-one setup: one local and one remote bridgehead server. This configuration is limiting, and multiple connectors must be load balancing and fault tolerant. X.400 bridgehead servers are configured through the local and remote X.400 names designated for the connector.
For all connectors, administrative tasks, such as content restrictions, delivery restrictions, and removing and disabling connectors, are performed using very similar administrative steps.
Enabling Content Restrictions
Content restrictions set priority, allowed types, and sizes for transferred messages by a connector. To enable content restrictions, use the following steps:
Enabling Delivery Restrictions
Delivery restrictions are used to accept or reject messages based on the sender's email address before being transferred over the connector. No restrictions are set, by default, allowing all messages to be delivered. To configure connectors to reject messages from specific senders, follow these steps:
Connectors can be disabled or removed at any time. To disable a connector, follow these steps: