The -- placeholder in the address space for the inbound Send connector represents the authoritative and internal relay accepted domains for the Exchange organization and is the literal character displayed. Any messages that the Edge Transport server receives for authoritative and internal relay accepted domains are routed to this Send connector and relayed to the smart hosts.
The -- placeholder in the list of smart hosts represents all the Hub Transport servers that are located in the subscribed Active Directory site and is the literal character displayed. Hub Transport servers that are added to an Active Directory site after an Edge Subscription has been established do not participate in the EdgeSync synchronization process. However, they are automatically added to the list of smart hosts for the inbound Send connector. If more than one Hub Transport server is located in the subscribed Active Directory site, inbound connections will be load balanced across the smart hosts
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This address space ("--") is only used on Send connectors configured on Edge Transport servers for sending messages to the Hub Transport servers. When you use this address space, all messages addressed to your accepted domains are routed through this connector.
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