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Configuring NNTP on an Exchange 2000 server

One of the most useful services on the Internet is Usenet. But how do you configure Exchange 2000 to host Usenet files? In this Daily Feature, Walter Glenn shows you what you need to do to make it work.

With a few simple steps, you can set up an Exchange 2000 server as a host in the Internet’s Usenet network and provide your Exchange users with access to the wealth of information available from newsgroups. Without a good understanding of how it works, though, the information in those newsgroups can quickly grow and overwhelm an Exchange server. As you probably know, connections to Usenet servers are accomplished using NNTP. In this Daily Feature, I’ll show you how to configure Exchange 2000 to support NNTP.

What are Usenet and NNTP?
Usenet is a distributed network of forums in which users hold threaded discussions with other users, much like you would in your typical public folder. Thousands of these newsgroups are available on the Internet and are maintained on Usenet servers around the world. The administrator of each Usenet server decides which of the available newsgroups will be hosted on that server. The administrators can also create new newsgroups. Usenet servers can be configured to push newsgroup information to other servers or to pull information from another server. Either way, this transfer is called a newsfeed. The Network News Transport Protocol (NNTP) defines how Usenet servers transfer the newsgroup information between them and how client software, referred to as newsreaders, accesses the information on those servers.

Exchange 2000 Server can be configured as a fully functional Usenet server. In previous versions, Exchange Server itself provided the NNTP service. In Exchange 2000 Server, the NNTP service is provided by Internet Information Server 5.0; however, you can manage much of its configuration using the Exchange System Manager tool.

NNTP support is enabled during a default installation of Exchange 2000 Server. Right after installation, standard newsreader clients (like Outlook Express) can access any newsgroups created on the Exchange server using NNTP, whether or not the Exchange server is configured as a Usenet server.

There are two ways in which you can create a newsgroup on an Exchange 2000 server. The first way is to use System Manager or a client such as Outlook 2000 to create an individual newsgroup. The second way is to configure a newsfeed and pull selected newsgroups from another Usenet server, creating new public folders to match those newsgroups in the process.

Creating a newsgroup with System Manager or Outlook 2000
To create a newsgroup with System Manager, first find and expand the NNTP virtual server on which you want to create the newsgroup. To the end user, a virtual server appears to be a completely separate server with its own newsgroup hierarchy. By using virtual servers, a single Exchange server can host several news servers simultaneously. You can find the virtual server in the Protocols container for the physical Exchange server on which the virtual server is located. Once the NNTP virtual server is expanded, right-click the newsgroup category inside and choose New | Newsgroup from the shortcut menu.

To create a newsgroup with Outlook 2000, simply create a new public folder inside the Internet Newsgroups folder in your folder list. The new newsgroup becomes instantly accessible to newsreader clients. You can also turn an existing public folder into a newsgroup by dragging it into the Internet Newsgroups folder.

Creating a newsfeed
Configuring a newsfeed, and thus configuring an Exchange server as a Usenet server, is a straightforward task. Sure, you could simply allow users to use Outlook Express to access a Usenet server provided by your ISP. But because there are so many thousands of newsgroups available (not all of which are appropriate in a corporate environment), setting up Exchange as a Usenet server provides a simpler, more reliable, more controllable, and less litigious solution since you can limit the actual newsgroups that are brought onto the Exchange server.

As with most other Exchange tasks, you create a newsfeed in System Manager using a wizard. Before you start creating a newsfeed, however, you should have the following information:
  • The name of the Usenet site to which you will configure the newsfeed (This name must be a fully qualified domain name, such as news.isp.com.)
  • The names or IP addresses of the Usenet servers on that site
  • The user name and password your Exchange server will use to log on to the Usenet site (Note that some Usenet sites require validation and others do not.)

When you have this information, you can launch the New NNTP Feed wizard by right-clicking the Feeds container inside the NNTP Virtual Server container and selecting the New | Feed command.

The first step you’ll take in the wizard is to enter the fully qualified domain name (FQDN) or IP address of the remote Usenet server. You’ll then need to specify the role that the remote server will play in the newsfeed. Your options are Peer, Master, and Slave. The Peer role is for servers that will share articles equally. It works roughly the same way that newsfeeds in previous versions of Exchange have worked. The Master and Slave roles allow you to set up a more sophisticated relationship between servers in which master servers identify newsgroup articles for slave servers. A master feed is configured on a slave server and a slave feed is configured on a master server.

The wizard then asks you if you want to create an inbound newsfeed, an outbound newsfeed, or both. The default setting is to create both, meaning that newsgroups will be pulled from and pushed to the remote Usenet server. If you want to create an inbound newsfeed, you must also specify whether you want to accept incoming messages—in which case the remote server pushes messages to the Exchange Server—or pull messages from that server. This choice primarily depends on the bandwidth that you can dedicate to the newsfeed and whether or not the newsfeed will occur over a dial-up connection. If you are using a dial-up connection or if you want to control the bandwidth and schedule used by the newsfeed, you configure a pull newsfeed.

Finally, you must specify the actual newsgroups you want to receive. By default, all newsgroups and articles inside those newsgroups are included. Since even one relatively active newsgroup can grow quite large, you want to trim this list down to just those few newsgroups to which you want to provide access.

Once created, an object for the newsfeed can be found inside the Feeds container, as shown in Figure A. You can configure the newsfeed using the object’s properties. Most of the property pages for this object hold the same information that you configured in the wizard.

Figure A
After you create a new newsfeed, you can configure its properties in Exchange System Manager.


Using expiration policies
Expiration policies define how an NNTP virtual server deletes old articles from newsgroups. No policies are defined by default. You can create a policy with the New NNTP Expiration Policy wizard that you start by right-clicking the Expiration Policies container and choosing the New | Expiration Policy command. During the policy creation, the wizard will ask you to name the policy, select the specific newsgroups the policy applies to, and indicate how many hours old an article should be before it is deleted.

Using NNTP virtual directories
A virtual directory specifies a physical location for storing newsgroup articles. You can create multiple virtual directories for a single NNTP virtual server (even for a single newsgroup), which allows you to span newsgroup articles across multiple physical locations. There are different types of virtual directories available, including a folder on the local computer, a network share, or even a public folder.

Each NNTP virtual server has two virtual directories by default. The first provides storage for internal NNTP files. The second provides storage for all NNTP newsgroup content. You can create other virtual directories by right-clicking the Virtual Directories container and selecting New | Virtual Directory. In the New NNTP Virtual Directory wizard launched by this command, you’ll specify the newsgroups that will be stored in the virtual directory and where the virtual directory will be located.

Conclusion
Setting up an Exchange server with a newsfeed gives you a great way to provide limited newsgroup access to your users without the hassles that come with full access. Configuring newsfeeds is a straightforward, wizard-driven process that is easy to set up and to maintain.

Editorial disclaimer
The authors and editors have taken care in preparation of the content contained herein but make no expressed or implied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed for any damages. Always have a verified backup before making any changes.

 
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