In Exchange 2000/2003, each Exchange server
had one or more SMTP virtual servers. These SMTP virtual servers
received inbound mail from other servers, from outside the
organization, or from POP3/IMAP4 clients. The SMTP virtual server could
be configured to host an SMTP connector for delivering messages to
external SMTP hosts or it could host a routing group connector (RGC)
for delivering messages to remote Exchange 2000/2003 routing groups.
Exchange Server 2007/2010 has replaced the SMTP virtual servers and SMTP connectors with send and receive connectors.
1. Receive Connectors
The receive connector is the point where inbound
SMTP mail is received on the Hub Transport server. Receive connectors
do not deliver outbound mail (unlike the Exchange 2000/2003 SMTP
virtual server). Each Hub Transport server automatically has two
receive connectors. These are the Default servername connector and the Client servername connector. Figure 1
shows the Exchange Management Console and the Server Configuration work
center. In the Hub Transport subcontainer, you can see each server that
hosts the Hub Transport role. The receive connectors for server EX2010
are shown.
The Client receive connector listens on TCP port
number 587, not TCP port 25. TCP port 587 is the alternate port for
POP3/IMAP4 clients to access SMTP, as per RFC 2476. The Client receive
connector is intended for receiving mail from non-MAPI clients such as
POP3 and IMAP4 clients. You would, of course, have to change the
non-MAPI client's outbound SMTP port in order to use this connector,
though some new POP3/IMAP4 client applications now default to port 587.
The Default receive connector is used to receive
inbound SMTP mail from other Exchange 2010 Hub Transport servers in the
organization. In Figure 2,
the Permission Groups properties of the Default EX2010 receive
connector are shown. These are the default permissions for the Default
receive connector.
Notice that the Default receive connector does not
accept connections from anonymous users. This means that you must
modify permissions before you use it to receive email from the
Internet; even though the receive connector is listening on TCP port
25.
You can also view the properties of a receive connector using the Get-ReceiveConnector cmdlet. Here is an example that displays all the properties of the Default EX2010 receive connector:
Get-ReceiveConnector "Default EX2010" | FL
RunspaceId :
f981d6a2-e04e-4fc8-a470-f7377e69e574
AuthMechanism :
Tls, Integrated, BasicAuth, BasicAuthRequireTLS, ExchangeServer
Banner :
BinaryMimeEnabled : True
Bindings : {:::25, 0.0.0.0:25}
ChunkingEnabled : True
DefaultDomain :
DeliveryStatusNotificationEnabled : True
EightBitMimeEnabled : True
DomainSecureEnabled : False
EnhancedStatusCodesEnabled : True
LongAddressesEnabled : False
OrarEnabled : False
SuppressXAnonymousTls : False
AdvertiseClientSettings : False
Fqdn : Ex2010.Contoso.com
Comment :
Enabled : True
ConnectionTimeout : 00:10:00
ConnectionInactivityTimeout : 00:05:00
MessageRateLimit : unlimited
MessageRateSource : IPAddress
MaxInboundConnection : 5000
MaxInboundConnectionPerSource : unlimited
MaxInboundConnectionPercentagePerSource : 100
MaxHeaderSize : 64 KB (65,536 bytes)
MaxHopCount : 30
MaxLocalHopCount : 8
MaxLogonFailures : 3
MaxMessageSize : 10 MB (10,485,760 bytes)
MaxProtocolErrors : 5
MaxRecipientsPerMessage : 5000
PermissionGroups : ExchangeUsers, ExchangeServers,
ExchangeLegacyServers
PipeliningEnabled : True
ProtocolLoggingLevel : None
RemoteIPRanges :
{::-ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff, 0.0.0.0- 255.255.255.255}
RequireEHLODomain : False
RequireTLS : False
EnableAuthGSSAPI : False
LiveCredentialEnabled : False
Server : EX2010
SizeEnabled : EnabledWithoutValue
TarpitInterval : 00:00:05
MaxAcknowledgementDelay : 00:00:30
AdminDisplayName :
ExchangeVersion : 0.1 (8.0.535.0)
Name : Default EX2010
DistinguishedName : CN=Default EX2010,CN=SMTP Receive
Connectors,CN=Protocols,CN=EX2010,CN=Servers,CN=Exchange Administrative
Group(FYDIBOHF23SPDLT),CN=Administrative Groups,CN=Contoso,CN=Microsoft
Exchange,CN=Services,CN=Configuration,DC=Contoso,DC=com
Identity : EX2010\Default EX2010
Guid :
e8eb2c53-de0b-4a94-98d1-f5d3965d6d58
ObjectCategory :
netlogontech.com/Configuration/Schema/ms-Exch-Smtp-Receive-ConnectorObjectClass:
{top, msExchSmtpReceiveConnector}
WhenChanged : 10/07/2009 5:10:38 PM
WhenCreated : 10/07/2009 5:10:38 PM
WhenChangedUTC : 10/07/2009 9:10:38 PM
WhenCreatedUTC : 10/07/2009 9:10:38 PM
OrganizationId :
OriginatingServer : DC.Contoso.com
IsValid : True
With few exceptions, you will usually not
need to create additional receive connectors, nor will you need to make
many changes to the existing receive connectors that are used
internally. The only situations that should involve creating new
Receive Connectors are when you need to accommodate the needs of a
custom application or server that needs to route email through your
Exchange servers. For example, you may have a monitoring server that
may need to send email internally to your server administrators. In
this case, you could use the default Receive connectors, but would then
have to customize them for that need. To avoid messing around with the
default Receive Connectors, most organization choose to create a new
Receive Connector that has a custom IP address range (which would allow
only the monitoring server to communicate) and custom permissions
(which would allow the monitoring server to relay email through your
Receive connector). This solution ensures that you have not,
inadvertently, prevented your organization from receiving email because
of misconfigurations on your default Receive Connectors.
