Release 10.1A: OpenEdge Getting Started:
WebSpeed Essentials

Multiple LAN development environment

Some development environments include several local area networks (LANs). For example, a company’s intranet might include two LANs—a Sales LAN and a Manufacturing LAN.

The common OpenEdge administration architecture includes a method for connecting NameServers to other NameServers. When a NameServer receives a request for an application service, it checks to see whether any of the WebSpeed brokers registered with it supports that application service. If none of its registered brokers supports that application service, the NameServer passes the request to other NameServers that it knows about.

Using this capability, you can link OpenEdge installations across the LANs that make up a wide area network. Figure 4–4 shows the products installed on a multiple LAN configuration.

Figure 4–4: Multiple LAN development environment

In this configuration, the NameServer machine, Saturn, is the central communication point that routes requests to the WebSpeed Transaction Servers on both LANs. Requests start from workstations, like Prometheus (which has OpenEdge Studio installed on it). A workstation passes the request to the Web server machine, Pandora, which has the WebSpeed Messenger installed. The Messenger asks the NameServer on Saturn to find a WebSpeed Transaction Server that can handle the request, by specifying an application service with the WService parameter.

Calypso and Hyperion both have the Transaction Server installed. The Transaction Servers are registered with Saturn’s NameServer. Saturn’s NameServer checks its list of registered Transaction Servers to see whether one supports the application service that can handle the request from Pandora’s Messenger. If one of them does, the NameServer passes its location back to the Messenger and the request is completed. The Transaction Server installed on Titan includes a NameServer. You can register this NameServer with Saturn’s NameServer as a NameServer Neighbor. If the WebSpeed Brokers on Calypso or Hyperion do not support the correct application service, Saturn’s NameServer passes the request to the NameServer on Titan to see whether the Broker registered with it supports that application service. If the Broker on Titan does support the application service, Titan’s NameServer passes its location to Pandora’s Messenger. Then the request is completed as normal.

For more information on how this works, see the section on using NameServer neighbors in OpenEdge Getting Started: Installation and Configuration .

Note that there are only two machines with data sources in this configuration—Hyperion, on the Windows side, and Atlas, on the UNIX side. Because the WebSpeed Transaction Server does not come with a database, you must install the Progress OpenEdge Enterprise RDBMS or the appropriate DataServer to connect to your non-OpenEdge database. The WebSpeed Agents on any of the Transaction Server machines in the configuration can access either data source.

To set up a multiple LAN configuration:

Install a Web server on Pandora.
Install the NameServer on Saturn.
Install the WebSpeed Transaction Server on Calypso, Hyperion, and Titan.
Install the WebSpeed Messenger on Pandora.
Install OpenEdge Studio or the WebSpeed Workshop on Prometheus and your other workstations, according to your development needs.
Install the appropriate data source components on Hyperion and Atlas. This depends on what you use as your data source:
If you use the OpenEdge Database, install the OpenEdge Enterprise RDBMS.
If you connect to a non-OpenEdge data source, install the appropriate OpenEdge DataServers. See the appropriate OpenEdge DataServer guide for details.

Beyond the basic installation

When you expect heavy loads on your network or want to increase its fault tolerance, you might want to add the load balancing option for the NameServer. If you deploy several WebSpeed Transaction Servers that support the same application service, you can use load balancing to control how the load is spread over them. See the "Understanding the NameServer’s load balancing option" section.

If you are going to use a non-OpenEdge database, you must install the appropriate DataServer on the Atlas and Hyperion servers.

Startup sequence

After you have installed and configured everything, you can start your WebSpeed environment.

To start a multiple LAN configuration:

Start the AdminServers on Saturn, Calypso, Hyperion, Titan, and Atlas.
Note: Once the AdminServers have started, you can use the Progress Explorer from any machine to start other components on these machines.
Start the data sources (and data server brokers, if needed) on Hyperion and Atlas in multi-user mode.
Start the NameServers on Saturn and Titan.
Start the WebSpeed Transaction Servers on Calypso, Hyperion, and Titan.
Start the Web server on Pandora.
Start an AppBuilder on a workstation (like Prometheus) as needed.
Start a Web browser on a workstation by choosing the WebTools from the AppBuilder’s Tools menu as needed.
Note: If one of the data sources fails, you should stop all the WebSpeed Transaction Servers that support applications that use that data source. Bring the data source back up and then restart the Transaction Servers. This helps ensure data integrity.