Managing Exchange Server 2007 Receive Connectors (Part 1)

Introduction

Exchange Server 2003 uses the SMTP Virtual Server that comes with the Operation System to control message flow. In Exchange Server 2007 the SMTP service bits are installed within the Exchange Server 2007 installation process. Because of this, we have two different components when we are talking about SMTP traffic in the Exchange 2007 architecture: the receive connectors and the send connectors. They are configured in two different places, the Send Connector is configured at Organization level and the receive connector at Server level. The receive connector is responsible for all SMTP incoming traffic which can originate from an external source, a client, a partner, or another Exchange Server and on top of that the receive connector uses authentication and some other features to manage all received connections.

By default Exchange Server 2007 has two new receive Connectors called Client Receive Connector and Default , where is the Netbios name of the Exchange Server. The default Receive connectors can be found under Server Configuration / Hub item using the Exchange Management Console, as shown in Figure 01. They can also be found using the Get-ReceiveConnector cmdlet through the Exchange Management Shell. By default any new Exchange Server can receive messages from other Hub Transport servers due the Default Receive connector which is named Default and is configured to receive traffic from any host, to any local IP address on port 25 but this traffic must be authenticated first.



Now we are going to create a new Receive Connector from scratch and during the process we will explain the available options that can be defined during the wizard. The server used in this article has two IP addresses: 172.16.171.11 and 172.16.171.12.

Each connector has a unique set of the following attributes: IP Address, Port number and remote IP Address range. These parameters are always validated during the New Receive Connector wizard. If you have an existent connector with the same values a new connector cannot be created.

In this article we are going to create an Internet Receive Connector using the second IP address of the server, as follows:

-Open the Exchange Management Console.

-Expand Server Configuration.

-Click on Hub Transport.

-Select the server name on the right hand side.

-In the Toolbox Actions. Click on New Receive Connector.

-Introduction. Let’s name this new connector using the Name field, and we can also select which kind of connector it is for (Figure 02). We have five options: Internet, Internal, Partner, Client and Custom and each one of them defines a set of authentication and permissions on the connector that we are creating. The choice of connector also changes the New Receive Connector wizard, so it is not the same wizard for all types of pre-configured connectors. In this article we are going to start playing with an Internet Receive Connector, so let’s click on Internet and click on Next.

Note:
If we choose a wrong type of connector we can always change the configuration afterwards. It is not necessary to recreate it due to choosing the incorrect option.


Figure 02

Okay, what if we had chosen Client, Partner or Internal instead of Internet? What would be the difference? The following table shows which changes will be applied for each type of receive connector chosen. We have three columns, the first one (During Wizard) shows which information will be required during the New Receive Connector Wizard; the second one (Authentication) shows what authentication method will be configured by default in the new Receive Connector and the last one (Permissions) shows which groups are marked in the Receive Connector permissions. Remember that all those values can be changed through the Exchange Management Console or Exchange Management Shell afterwards.


We will go over Authentication and Permissions later on in this article series, for now let’s finish our Internet Receive Connector.

Local Network Settings. Let’s use only the second IP address of the local server on port 25. We are also going to use the mail.andersonpatricio.org as FQDN, as shown in Figure 03. This name will be displayed when a connection is established with this Receive Connector. Click on Next.


Figure 03

New Connector. A summary of our choices made so far. Click on New to create the Receive Connector.
Completion. Final screen of the new receive connector wizard with all the information provided during the wizard and the cmdlet used to create it. Click on Finish.

Okay, these are the steps required to create a new receive connector; we can do the same using the Exchange Management Shell. To create we have to use the New-ReceiveConnector cmdlet. In this example we are going to create the same connector described in the steps above:

New-ReceiveConnector -Name “Connector Name” –Usage:Internet –Bindings:: -fqdn: ‘’ –Server

Testing the new Receive connector…

Okay, we have just created our new connector. We can start testing it using the following command: telnet 172.16.171.12 25 where 25 is the port that will be used (Figure 04). The connection will be made and the FQDN name that we defined in our new Receive Connector will be shown. If we try to connect using the IP address 172.16.171.11 we will receive a different prompt because it is a different connector. Our Internet connector is only listening on the 172.16.171.12 IP address.



Figure 04

Conclusion
In this article we have seen how to create a receive connector and we also saw that a Receive Connector must be unique in at least one of these attributes: IP Address, port, Remote IP Address, in order to be created. In the following article we are going to use the telnet utility to test a Receive Connector and also take a look at some security and throttling configurations.