Before you begin | SMTP | POP3 | HTTP | NNTP
Connecting Microsoft Exchange Server to the Internet is a very quick and simple process. Exchange Server 4.0 supports the SMTP protocol through the Internet Mail Connector, and Exchange Server 5.0 supports SMTP, POP3, HTTP, and NNTP natively. This white paper covers the minimal steps you need to follow to configure this support. The format is equally minimal - no explanation or justification of any of the steps is included. For further information on any of these steps, you should consult the materials indicated in the last section. Before you begin Make sure that the Exchange Server that you intend to connect to the Internet is running properly. Exchange clients with mailboxes on this server must be able to send mail to each other. Also make sure that the TCP/IP network protocol is installed on the server. If you are configuring Exchange Internet support on a server that is already connected to the Internet through your corporate LAN, you can skip to step 3 below. Otherwise, follow Steps I and 2 to set up a very basic
1. Contact an Internet Service Provider (ISP), such as NuNet Inc. Tell them you want to set up a permanent connection to the Internet, that you will be running your own SMTP, HTTP, and NNTP servers, but that you want them to run DNS for you. They will want to know what sort of hardware and software you are using on your LAN, whether you need a router and CSU/DSU, and what speed connection you need. Unless you know differently, tell them you want to buy the connection hardware from them, that you want a connection guaranteed at 56Kbps, and a fixed Class "C" IP address. In addition, tell them that you want them to take care of all the logistics' including working with the local telephone company for the line, registering your domain name, and configuring your router. Pick a domain name for your email (such as company.com), and a name for your mail server (such as mail.company.com). If you believe you will have very heavy Internet traffic, you might want to get a higher speed connection, but that will cost significantly more. Most ISP's will recommend a higher speed link if you tell them you will be running a news server, but that is not really necessary if you will only be pulling down a few newsgroups. You can also run your own DNS, but that is outside the scope of this document. If you can't cost-justify a full time connection, you can tell NuNet that you will be dialing up on a periodic basis to download mail. In that case, you should set up RAS on your Exchange server and create a phone book entry for their Point of Presence (POP). You should consider an ISDN connection, but a modem connection can also work for low volume situations. For more details on these steps, see "Appendix A, Connecting with an Internet Service Provider", in reference (A) below.
2. Once NuNet has set up your account, the phone company has installed the line, and the ISP has delivered and installed any hardware you are buying from them, you may need to reconfigure the IP addresses on your LAN to match the Class "C" address obtained from NuNet. Do this before continuing.
3. You are now ready to begin configuring your Exchange Server. Do the following tests from a command prompt running on the Exchange Server. If you have a full time connection to the ISP, you can proceed to this step immediately; if you have a dial up connection, connect to NuNet over RAS before you try this step. At this point, test connectivity to the Internet by pinging a known host, for example the NuNet server at mail.nni.com. The following shows a successful result: C:\users\default>ping mail.nni.com Pinging 216.107.0.100 with 32 bytes of data: Reply from 216.107.0.100: bytes=32 time=341ms TTL=115 Reply from 216.107.0.100: bytes=32 time=280ms TTL=115 Reply from 216.107.0.100: bytes=32 time=281ms TTL=115 Reply from 216.107.0.100: bytes=32 time=280ms TTL=115
4. If you got anything substantially different, such as "Destination Host Unreachable", or "Request Timed Out", you need to debug your TCP/IP configuration before going any further - check out the protocol installation and your router or PAS configuration. If you had the ISP configure your router, call their technical support line. If you successfully pinged the host by IP address, now try to ping a host by name, for example dns.microsoft.com. The following shows a successful result: C:\users\default>ping dns.nni.com Pinging dns.nni.com [216.107.0.3] with 32 bytes of data: Reply from 216.107.0.3: bytes=32 time=300ms TTL=115 Reply from 216.107.0.3: bytes=32 time=281ms TTL=115 Reply from 216.107.0.3: bytes=32 time=280ms TTL=115 Reply from 216.107.0.3: bytes=32 time=881ms TTL=115
5. If you got a message such as "Bad IP address", you need to debug your TCP/IP configuration before going any further - check out the DNS settings to make sure that you have an entry for a valid DNS server. If you had NuNet run DNS for you, call their technical support line. If you successfully pinged the host by name, this means that TCP/IP on your server and the DNS are working, and you can continue. At this stage, TCP/IP is adequately set up to allow us to configure the Exchange Server to send outbound mail.
6. Find out the IP address and the TCP/IP host name of the Exchange Server. Suppose the server is mail.nni.com at 2116.107.0.3. Try to ping this by IP address. If you cannot, you did not find out the correct IP address for your server - check the TCP/IP properties in the Control Panel Network applet.
7. Ping your Exchange Server by name. This is critical - all the Internet protocols require that clients and other servers on the Internet can find your system by name. If this fails, contact whomever is running DNS and tell them to add an Address ("A") record for your server (mail.company.com) into the DNS. Again, this may be someone in your own company, if you are running your own DNS, or it may be someone at NuNet.
8. You need to advise other mail servers on the Internet to forward mail to your Exchange Server. Suppose you want to receive mail as user@companycom. Tell the DNS administrator to add a Mail Exchanger ("MX") record for your domain (company.com) to the DNS for this purpose if it is not already there.
9. Test the MX record using NSLOOKUP, a utility provided with Windows NT 4.0. (If you are running NT 3.51, you will need to find a third-party vendor of this product.) From a command prompt, load NSLOOKUP, type "set type=MX" and hit Enter. Now enter your company's email domain name, such as company.com. A successful result would be one that returned the host name of your Exchange Server, mail.company.com, as in the following example: C:> NSLOOKUP Default server: ns.nni.com Address: 216.107.0.3 >set type=mx >company.com Server: ns2.nni.com Address: 38.9.92.23 Non-authoritative answer: Company.com MX preference = 10, mail exchanger=mail.company.com
10. The default server should show the name and IP address of the DNS server that is set up in your TCP/IP configuration, mentioned in steps 5 and 6 above. Depending upon whether the DNS server you point to is the main DNS server for your company, you will get either an authoritative or a non- authoritative answer - this is irrelevant. If you get any line that shows that the MX preference for your company (company.com) is your Exchange Server (mail.company.com), you are OK. If you do not get some such line, you will not be able to receive inbound mail and need to have the DNS administrator correct this before continuing. If this is working, TCP/IP is adequately set up to allow us to configure the Exchange Server to receive inbound mail.