Progress
Installation and Configuration Guide
Version 9
for Windows
Terminology
This section introduces the terminology used to describe client/server configurations.
Application Workstation
An application workstation is any node that runs one or more Progress clients. For example, Windows NT is a multi-processor, so you can start more than one client on an application workstation. Depending on its operating system and configuration, an application workstation might run local clients and servers as well.
Database Server Machine
A database server machine is any node that runs one or more Progress servers for local or remote Progress clients.
Network File Server
A network file server is any node that provides shared services including file, printing, and security services to other nodes, including application workstations and database server machines. A network file server usually provides these services by allowing other nodes to access its local files and printers as if they were local to the other nodes. For example, Progress clients can run application procedures and Progress servers can access database files stored on a remote network file server.
A network operating system (NOS) is a network environment that includes one or more network file servers that provide a common set of resource sharing and security services to other nodes. A network file server usually runs the kernel of an NOS, the program that controls access to shared network resources. Depending on its operating system, a network file server might also run one or more Progress database clients and servers.
Although Progress Software recommends that you store the database on a disk locally attached to the database server machine, you can store the database on a network file server. Clients can access shared application code and communicate with the database server. Depending on your application and network environment, however, you might lose database integrity.
Note that Progress often runs in local area networks (LANs) that have no network file servers. On these LANs, application workstations can access only locally stored procedures, and database server machines can access only locally stored databases. However, the application workstations and database server machines can communicate with each other as remote processes.
Single-process Database Server Machine
A single-process database server machine is a node that runs only one server process for each database, providing access to that database for self-service clients only.
Multi-process Database Server Machine
A multi-process database server machine is a node that runs multiple server processes for each database, providing multiple data paths to the database. Each server queues and runs requests for one or more clients. A separate broker process starts a new server for each additional client (or set of clients, in specified increments) that access the database. All nodes that run operating systems with shared memory run as multi-process database server machines. Progress supports multi-process database server machines on Windows nodes. For more information, see the "Shared-memory Configurations" section.
You can dedicate all the resources of a database server machine to run database servers. However, depending on your application and operating system, you can also run local clients and remote clients for other database server machines.
Copyright © 2004 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095 |