[Editor's note: This is the final article in our three-part series on how server connections work. This time, you'll learn about some specific connection scenarios, and how to use Server Connection documents to extend the reach of your Notes client. The first article focused on all of the connection types and how Notes uses them to connect to a Domino server. The second article discussed how passthru can make connecting to servers a road warrior's dream, and can make LAN connections easier as well. ]
Overview
Every time you open a database on your desktop, your Notes client must first find an address for the server that hosts that database, then send a request to the server to open a connection. Sending your Notes client to an address out across the network is like sending somebody to an address in the real world. Most of the time, you won't even have to tell them the exact address, because they'll already know it, or know how to find it. Sometimes they'll have to make a guess at it. And on rare occasions you'll have to write out the address and maybe even draw a map to help them get there.
Notes works pretty much the same way. Most of the time it knows how to get there -- when you click on an icon to open a database, Notes reads the common name of the server in the database properties, asks your home server for the network address of the server, and then uses it to send a connection request. Occasionally Notes has to make a guess, and it is programmed with several methods of making very smart guesses. On rare occasions, though, Notes can't find the address on its own. It needs you to draw a map. And that's what a Server Connection document is -- a map you draw for Notes to tell it the route to follow to reach a server.
You create and save these address documents for servers in your Personal Address Book (names.nsf), the same place you save address documents for people and groups. But because Notes needs different kinds of information to make different kinds of connections you can create five types of Server Connection documents -- Dialup Modem connections (the type you're probably most used to seeing), Local Area Network connections, Passthru connections, Hunt Group connections, and Remote LAN Service connections.
There are many times when creating a Server Connection document can solve a problem -- or take advantage of an opportunity to make Notes easier or faster to use:
- Create a Server Connection document to specify the address of a server unknown to your home server. (For more on the role of the home server, see "Making Server Connections in Notes." An example of this type of Connection document is given below.)
- Take advantage of a passthru server. Passthru makes a server an active intermediary between a Notes client and a remote server. Workstations and other servers can use a passthru server as a stepping stone to connect to another server that doesn't share a common protocol. (For more on passthru, see "Server Connections: Just Passing Thru.")
- Speed up the process of connecting to a server. Notes automatically tries several ways of creating a server connection. Some of these execute entirely on the client PC, and some involve sending requests across the network and waiting for responses. Server Connection documents are local, so they are checked early in the connection process and execute quickly. Even though Notes may be able to make a complex connection automatically, a Server Connection document may improve performance.
- Pass information to Notes that it uses to control external programs. A Server Connection document of the Remote LAN Service type can hold the login and password information that Notes needs to create a connection to a remote access server running on the network that hosts your Domino servers. When you create this document, Notes can control the dialer program that runs on your PC (Microsoft calls it Dial-Up Networking, while Apple calls it Appletalk Remote Access) and connect to the access server. (The Connection document overrides any other login information, if any, that would otherwise be used by the dialer.) Once connected, it can function just as if your PC were connected directly to the LAN.
If you're a Notes administrator, you probably know a great deal about server connections, because the various types of server connections are the tools an administrator uses to configure the relationships between servers within a Notes site. Most of that work is involved in setting up server-to-server communications by creating Server Connection documents -- this time, in the Public Address Book. The principles behind these Server Connection documents are very similar to those for client-to-server connections. Server-to-server connections can help users get access to information, and can improve the performance of the system in making connections. The key to these benefits is often the deployment of a passthru server, or the implementation of passthru on an existing home server. (For more on this, see the sidebar "Setting up a passthru server.")
While handling server-to-server connections is a job for an administrator, individual users can use Notes more effectively by creating several kinds of Server Connection documents on their own workstation (often with some help required from an administrator, to be sure). Here are some recipes for creating several types of Server Connection documents, with some examples of when and why you might use them.
LAN Connections: Getting doclinks to work across domains
A local area network is the native habitat of Notes. Most users connect to Domino servers across a LAN, and the Notes client doesn't need much help to make most connections -- it takes a programmed series of steps to find the address of the server where the target database resides. First it checks its own resources -- servers it has Server Connection documents for, or it has connected to recently. If it doesn't find an address, it will ask the home server for help by making a name service request. If the home server can't provide the address, then the client will probe the network, making an educated guess at the server address based on the address of the client. (For more information on this process, see the sidebar "How Notes Makes a Connection.")
Occasionally, though, Notes will fail to find an address, even though the destination server is physically connected to the same network as your client, and running a common network protocol. For example, let's say you receive a doclink in an e-mail message that points to a database on a server in another Notes domain. When you click on the doclink, you'll probably get the message "No path to server found." Why would the connection fail? Probably because your client didn't have a Server Connection document for the destination server, your home server didn't have a Server document that contained the address, and network probes didn't work because the client's address, based on its domain, is different from the server's.
So, how can you get the doclink to work? When you're on the same network and running the same protocol as the destination server, all you need to know is the address of the server. Then, you can create a Server Connection document of the Local Area Network type that tells Notes exactly how to get to the server. To do this:
- If necessary, right-click on the doclink to find out where it was supposed to go. The "Hint" should show the server name.
- Find out the address for the server. One way you can do this is by checking if you have a copy of the other domain's Public Address Book on one of your servers (which is very likely if the other domain is still a part of your organization). Then, you can simply open the Server document for the server, and find out its address in the Network Configuration section. Another option is that you can ask the server administrator for its address.
- Now, create your Connection document. Open your Personal Address Book and click Add Connection. Select "Local Area Network" as the connection type.
- Choose the LAN port for the connection, and enter the full hierarchical name of the destination server.
- Expand the Advanced section, and enter the destination server address.
- Save the document.
If the address is correct, and the destination server is connected to the network and is running the same protocol that your client used to make the connection request, then when you click on the doclink again, the database will open.
A Server Connection document may also help in situations where the server connection process is going consistently wrong. Notes may be consistently sending out network probes that find a server with a matching common name, but not the server you are searching for -- for example, you are looking for Sales/East/Acme, but you find Sales/West/Acme instead. Notes always checks for Server Connection documents at the start of its search for an address, so you can override the default process that's returning the wrong result by creating an explicit Server Connection document that describes exactly what port to use, and what the destination server's address is.
Passthru: Getting from A to B through C
But what if the destination server isn't running the same protocol as your workstation, or isn't connected to the same network? You may still be able to connect to it through a passthru server. This is the job of passthru servers -- to provide access where it isn't otherwise possible. To do this, passthru servers may run multiple network protocols and translate between them, and they may even be connected to multiple networks, providing a bridge for Notes data.
If your client runs only TCP/IP and the doclink in your e-mail points to a destination server that runs only SPX, you can connect to that destination server by using a passthru server that is running both TCP/IP and SPX. You need to create a Server Connection document of the Passthru Server type. To do this:
- This time, ask your administrator for the name and address of a passthru server to use.
- Now, create your Connection document. Open your Personal Address Book and click Add Connection. Select "Passthru Server" as the connection type.
- This time there are two fields for server names -- one for the destination server, and a new one for the passthru server. Fill them in.
- Expand the Advanced section and you'll see that there's no place to enter an address for the destination server as you did in the Local Area Network document. This is because you don't have to know this address -- the passthru server does. Save the document.
- While you don't need to tell Notes the address of the destination server, you do need to tell it the address of the passthru server you intend to use to get there (unless the server name is sufficient, of course). To do this, create a second Server Connection document -- this one of the Local Area Network type. Enter the name and address of the passthru server, and save it.
There are a couple of refinements you may want to apply to the Passthru Server Connection document:
- In Step 3 above, you entered the hierarchical name of a particular destination server -- Alpha/Marketing/Acme, for instance, would specify the server named Alpha in the organizational unit named Marketing within the domain named Acme. However, you can instead use an asterisk as a wildcard character in the destination server name field. And, beginning with Release 4.6, you can also use an asterisk in the destination server address field. This allows a passthru server to serve as a domain-wide resource. By using a wildcard specification (like */Marketing/Acme) in the destination server name field of your Server Connection document, that single document can give you access to all the servers in the remote domain.
- In the Advanced section you'll see a field labeled Usage priority. Notes uses this field to set the order in which it tries its various methods of searching for an address. If you set this field to Normal, Notes will use the passthru server named in this document to make connections to all servers in the domain identified by */Marketing/Acme. If you set the Usage priority to Low, Notes will try to connect to the server directly over the LAN first, and only if that fails, will it use passthru.
Internet Connection: Accessing your Notes mail across the Internet
Server connections of the LAN type aren't very exciting, because they're mostly direct connections. Passthru connections are more complex. But for sheer dramatic impact (and real usefulness) there's nothing quite like seeing your Notes mail open up across an Internet connection. If you have a high-speed Internet connection at home like the service provided by some cable TV companies, accessing Notes databases on your company's servers can be almost as fast across the Internet as it is across the LAN.
This isn't something you can do simply by creating a Server Connection document. Like setting up passthru servers, it takes planning and work by an administrator. And because it requires making a passthru server or even your Notes mail server accessible from the Internet, there are security implications that your company will doubtless want to weigh carefully.
But if your home server (or a passthru server that can connect to it) has an Internet connection and an IP address and domain name, the rest is easy. Let's take as an example the more complex of these cases, where you must use a passthru server to reach your mail server. You'd use the following steps:
Step 1: Make sure your PC is set up correctly
- First of all, make sure your computer is properly set up to access the Internet and use the TCP/IP protocol. If you're reading this Notes.Net article in a Web browser, you're all set.
- Make sure Notes is properly installed on your computer, and that your ID file is available and active.
Step 2: Create a new Location document in your Personal Address Book
- Create a new Location document and set its Location type field to Local Area Network. And under Ports to use, check only the TCPIP box. Don't select a COM port. (Do this even though you may be making a dial-up connection to your Internet service provider. You're telling Notes to behave as if it were on a very, very big version of your office LAN running the TCP/IP protocol -- which, in fact, it is.)
- Enter the name of your mail server in the Home/mail server field. If you'll be connecting directly to this server, that's all you have to do. If you'll use a passthru server to reach the mail server, enter its name in the field for Passthru server.
- Give this Location document a name that identifies its purpose, like "Mail via Internet," and save it.
Step 3: Create a Server Connection document
The type of Server Connection document you need to create depends on how you'll connect to your mail server -- either through a direct connection, or through a passthru server.
- If you're making a direct connection to your mail server, create a single Local Area Network Connection document with your mail server as the destination and TCP/IP as the LAN port.
In the Advanced section, enter your mail server's TCP/IP address. And in the Only from Location(s) field, enter the name of the Location document you created in Step 2. (If your workstation is a laptop that you also take to the office and connect directly to the LAN, this step will keep Notes from getting confused about which LAN Connection document to use for your mail server. Select the Office location when you're in the office, and Notes will ignore this new document. Select the new location when you're at home, and Notes will then use this document.) Save the document.
- If you're using a passthru server to get to your mail server, you have to create two new Server Connection documents:
- First, create a Passthru Server Connection document, and enter the passthru server you'll use, and your mail server as the destination. In the Advanced section, set the Usage priority field to Normal, and in the Only from Location(s) field, enter the name of the Location document you created in Step 2. Save the document.
- Next, create a Local Area Network Connection document with the name of your passthru server as the destination, and TCP/IP as the LAN port. In the Advanced section, enter your passthru server's TCP/IP address. And in the Only from Location(s) field, enter the name of the Location document you created in Step 2. Save the document.
Step 4: Connect to your mail database
To connect to your mail database, first dial up your Internet service provider. Then, from within Notes, make sure you are using the new Internet Location you created (Notes displays your current Location in the lower right corner of the screen -- click on it to select from the list of available Locations). Then click on your mail icon. Notes will follow the map you've drawn in the Location and Server Connection documents and -- if you've done it right -- open your mail.
(These instructions are necessarily brief. If you need more information on setting up connections to the Internet, see the Domino Administration Help. For more ideas on Notes and the Internet, check "The Internet Cookbook.")
Dial-up Connections: Things go better with passthru
Anyone who has ever tried to access databases from more than one server while on the road knows why passthru was invented. The process of making a dial-up connection to one server to check mail, then disconnecting and dialing up a separate connection to another server to replicate a database, can be time-consuming even under the best of circumstances. Passthru lets one connection do the work of many, and saves time and frustration in the bargain.
As stated earlier, your administrator must set up the passthru servers for your organization. Typically, an administrator dedicates at least one server on the LAN as a passthru server. That server then runs all the LAN protocols and has several modems available for dial-up use. The passthru server can establish a connection to any server on the LAN and translate between the network protocol and the X.PC protocol Notes uses for dial-up connections. If you are a remote user who dials into this server, you have potential access to all the servers on the LAN, depending on your access rights.
If you're a road warrior who makes only dial-up connections to servers (that is, it runs only the X.PC protocol and uses only the Modem ports like COM1 or COM3), setup is straightforward. All you need to do is create a Server Connection document of the Dialup Modem type for the passthru server, and enter the passthru server name in the field for Default passthru server in your Location document.
But suppose you work in a small district office of a large company. Your office has its own LAN, but you need to connect to servers at the home office, which requires making a dial-up connection through a passthru server. The setup outlined in the previous paragraph will work, but a little fine-tuning based on some knowledge of how Notes searches for a connection can yield a noticeable performance improvement. Here's why:
Because your workstation is connected to a local area network, a network port is enabled in your Location document. Notes will first try to make the connection using this port, and it will follow all the steps outlined in the sidebar "How Notes Makes a Connection." The Dialup Modem connection in our example is set to Low, which means that Notes will try other methods of making the connection -- some of which can take a noticeable amount of time -- before it uses this Server Connection document.
You can avoid this wait if you create Server Connection documents for the destination servers you use at the home office. Set their Connection type to Passthru, set their Usage priority to Normal, and specify the passthru server on the home-office LAN as the passthru server. If the home-office servers are grouped in a Notes organizational unit -- a Notes Network or a domain -- you should be able to use a wildcard for the destination server name and this one Server Connection document should provide access to all of them.
Remote LAN Service: Putting Notes in the driver's seat
Remote Access (RAS) connections are not a feature of Notes, but a method of extending network protocols out across a dial-up connection, so that a remote client can connect to a RAS server on a LAN and have the same access to resources on the network (such as Domino servers) that it would have if it were connected directly to the LAN. RAS provides many of the same benefits to Notes users as the dedicated passthru server configuration we looked at above, and in addition, it provides access to other network resources, such as database servers or Internet access, as well.
The early popularizers of this technology were hardware vendors such as Shiva and Ascend. More recently, Microsoft and Apple have included RAS in their operating systems: Dial-up Networking for Windows 95 and NT users, and Appletalk Remote Access for Macintosh users.
These client applications are called dialers. If you make a dial-up connection to a Domino server on a network that provides OS-based RAS services, you can give your Notes client control of your operating system's dialer program, allowing it to automatically initiate a dial-up connection when you click on a database icon, and break it when you close the application. You do this by creating a Server Connection document of the Remote LAN Service type:
- Make sure RAS services are working properly on your machine and you have the right connection information by setting up and testing a connection to your RAS server outside of Notes.
- Create a new Server Connection document. Select "Remote LAN Service" as the Connection type.
- In the Destination Server name field, enter the name of a server or a wildcard entry designating a group of servers.
- In the field labeled "Use LAN port:" select the network protocol that your workstation and the LAN are running. (For an Internet connection, use TCP/IP.)
- In the Remote LAN service field, select the type of RAS related to your operating system -- Notes will work with Microsoft or Apple.
- Fill in the details of the dial-up connection: the name of the RAS server on the LAN, your login name and password, and the phone number for the RAS server.
- Save the document.
A Remote LAN Service connection is particularly useful if you have access to Notes via the Internet. Once you have your Internet connection working, you can change your Server Connection document to one with a connection type of "Remote LAN Service," which allows Notes to manage the call to your Internet Service Provider. Click your mail icon and Notes will dial the phone call for you.
Summary
Server Connection documents are a powerful tool for Notes. Their functions are more specialized than basic tools such as Location documents or the Replicator panel, and as a Notes user you may not use them as often. But as your organization's Notes infrastructure becomes larger and more complex, you will find that they are the right tools for the job of solving problems of access to information. And if you venture off the LAN and need to make more exotic kinds of connections through RAS servers or hunt groups or over the Internet, Server Connection documents will be come a standard part of your toolkit.
ABOUT GEORGE
George Sprott was working as a physicist when he caught the computer bug. Once afflicted, he joined the high tech world to further study the occult arts of programming, debugging, and software project scheduling. He joined the networking group at Iris in 1993 where he was permitted to perform development in the arcane areas of passthru, Remote LAN, and "why can't I reach that server." As therapy for his long addiction to programming, he goes sailing, renovates his house, and occasionally contributes to technical articles about Notes.