TransportServer.ExternalIPAddress Property

Syntax

'Declaration
<ParameterAttribute(Mandatory := False)> _
Public Property ExternalIPAddress As IPAddress
    Get
    Set
'Usage
Dim instance As TransportServer
Dim value As IPAddress

value = instance.ExternalIPAddress

instance.ExternalIPAddress = value

[ParameterAttribute(Mandatory = false)]
public IPAddress ExternalIPAddress { get; set; }

Remarks

The ExternalIPAddress property specifies the IP address that is used in the Received message header field for every message that travels through the Edge Transport server or Hub Transport server. The IP address in the Received header field is used for hop count and routing loop detection. When an Edge Transport server is protected by a router or firewall that uses Network Address Translation (NAT), NAT disrupts the hop count and routing loop calculations of the Edge Transport server.

When the Edge Transport server is protected by NAT, the RFC 1918 private, non-routable IP addresses typically used by the server's network adapters don't match the public, routable IP addresses defined in the domain's public DNS MX records. The IP addresses that are assigned to the internal or external network adapters of the Edge Transport server can be determined by using the Get-NetworkConnectionInfo cmdlet.

The IP address specified by the ExternalIPAddress property overrides the external network adapter's actual IP address. Typically, you set the value of the ExternalIPAddress property to match the value of your domain's public MX record. The default value of the ExternalIPAddress property is blank. This means that the actual IP address of the external network adapter is used in the Received header field.

See Also

Reference