Home

	Expand Search

Server Administration Guide for DirectConnect

Chapter 1 Introduction

Chapter 1

Introduction

This chapter introduces basic DirectConnect concepts and describes the DirectConnect Server external files.

This chapter covers the following topics:

• DirectConnect overview

• Server external files

The CIS functionality in ASE was formerly known as OmniConnect. Any reference to OmniConnect in this document applies to ASE/CIS.

DirectConnect overview

DirectConnect is an Open Server-based Sybase product that provides consistent connectivity to non-Sybase data sources. In particular, it provides access management, copy management, and remote systems management.

DirectConnect consists of a DirectConnect Server, service libraries, and services. The following sections describe these components.

The DirectConnect Server

The DirectConnect Server routes incoming client requests and provides a set of support functions that includes logging, tracing, and message handling. You can use it to add and delete services, configure service properties, and manage other features.

The server is designed to operate with a variety of related Sybase software products, including:

• Open Client(TM)

• Custom Open Client applications

• Adaptive Server Component Integrator Services (ASE/CIS)

• MainframeConnect for DB2/MUS-CICS

• Enterprise Application Server (EAS)

• Adaptive Server Enterprise (ASE)

• Replication Server

• DirectConnect Manager

• jConnect

• Open ServerConnect

For more information about how each of these Sybase products operates, see the appropriate product documentation.

DirectConnect service libraries

Each DirectConnect service library provides a specific function. The server provides the framework within which the service libraries operate.

A service library is defined by:

• The SQL requests it supports

• The remote procedure calls ( RPCs) it supports

• The global variables it supports

• The set statements it supports

• The specific configuration properties it recognizes

• The specific Open Server(TM) events that it can process

Many named service libraries are available through DirectConnect, including the following:

• Access Service Library

  This service library accesses non-Sybase data contained in a target database system. Each access service library supports a common set of features, so that all applications using the features work consistently, regardless of the target database system.

  For information about access service libraries, see the appropriate DirectConnect Access Service User's Guide for your database system.

• Administrative Service Library

  This service library provides remote management capabilities. The Windows-based component that connects to this service library and enables you to easily configure and manage DirectConnect is the DirectConnect Manager.

  For information about the administrative service library, see the online help and table of contents for DirectConnect Manager.

DirectConnect services

A service is the pairing of a service library and a set of specific configuration properties. Within each service library is a collection of configuration sets containing properties that define how each service behaves.

The following rules define the relationship between service libraries and services:

• Each service has one configuration set and is always associated with a specific service library.

• All services within a given service library share the same configuration properties. The descriptions of the properties are the same for all such services.

• You can assign different property values to different services within a service library.

• A single service library can support multiple services.

• A DirectConnect Server provides the framework within which the service libraries operate.

The DirectConnect Server routes each client request to the appropriate service. The routing process takes one of two forms:

• With direct resolution, you specify the exact name of the service. If the service is defined correctly, the DirectConnect Server matches the request with the service.

• With service name redirection, you map your service connections. Client requests are routed to assigned services based upon user profiles. This feature allows you to centrally manage client access to services.

For information on service name redirection and examples of how it works, see Chapter 5, "Using service name redirection" .

Configuring DirectConnect properties

You can configure DirectConnect properties on the server level, the service library level, or on an individual service level. To help you do this, DirectConnect configuration properties are grouped as follows:

• In server configuration files, which consist of the properties that manage a particular DirectConnect Server.

• In service library configuration files, which consist of general library configuration values as well as configuration sets for all services associated with a particular service library.

• In service configuration sets, which consist of properties that define a particular service. Service configuration sets are stored in the service library configuration file.

When you install a DirectConnect Server, the default configurations allow the server to run. For each service you create within each server, you will need to provide additional configuration properties that define the connectivity to your target database system. For information on configuring the DirectConnect Server, see Chapter 4, "Configuring the server" .

Services can be set to be enabled at start up through a configuration setting. If this value is set to no, then you will need to manually enable the service before it can be used. For information on configuring service libraries and services, including instructions on creating new services, see the appropriate DirectConnect Access Service User's Guide for your database system.

Sybase recommends that you configure properties using a text editor or DirectConnect Manager. Consider the following:

• Changes that you make with a text editor do not take effect until you restart the server.

• Most changes that you make with DirectConnect Manager can be made to take effect immediately.

• You can use DirectConnect Manager help as a guide to the properties that can be changed, as well as the valid values for each property.

• DirectConnect Manager can perform all of its management functions remotely. With DirectConnect Manager, there is no need to have access to the DirectConnect Server machine or directory.

• DirectConnect Manager can provide management services to multiple servers at the same time, including the ability to copy service configurations from one server to another.

For more information about DirectConnect Manager, see the following section.

Using DirectConnect Manager

DirectConnect Manager is a Windows-based Sybase Central plug-in application that allows you to configure and manage Sybase DirectConnect servers interactively. DirectConnect Manager interacts with one or more DirectConnect servers to provide configuration and management capabilities from a client machine.

You can perform the following tasks with DirectConnect Manager:

• Manage DirectConnect servers on multiple platforms

• Change configuration properties of DirectConnect servers, service libraries, and services

• Create and copy services by copying an existing service and giving it a unique name

• Start, stop, and delete services (from a remote site, DirectConnect Manager is the only way you can start a service)

• Test the availability of a data source by creating a connection to it

• Retrieve a DirectConnect server log file or a subset of the log, and view log file messages with a text editor

• Update DirectConnect server connection information

• View the status of a service and data source on the desktop

DirectConnect Manager graphically represents each DirectConnect object on a tree list or an "icon map," a customizable workspace where you can add or remove objects. When you add a DirectConnect server to DirectConnect Manager, its server name, service library, and any services appear on the tree list or the icon map.

To issue a command in DirectConnect Manager, you simply select a server, service library, or service object, and choose a menu item or keyboard shortcut. Which commands you can use depends on the object you chose.

DirectConnect Manager communicates with DirectConnect Servers asynchronously, which means you can continue to use DirectConnect Manager while a command is being processed.

For more information about DirectConnect Manager features, use the DirectConnect Plug-in Help available under the Help menu option.

Directory structure

Following are diagrams of directory structures for UNIX and Windows NT platforms.

Notice the following:

• Each server that is created has its own cfg and log files

• The UNIX directory structure contains an extra subdirectory called lib

Server external files

The DirectConnect Server manages external files that reside in various subdirectories. For information on the DirectConnect directory structure for your installation, see the appropriate DirectConnect Installation Guide for your database system and platform.

Following are brief descriptions of the server-managed external files:

Server configuration file

The server configuration file server.cfg contains all server configuration information. It resides in the server cfg subdirectory. For more information on server configuration, refer to Chapter 4, "Configuring the server" .

Service library files

One executable file is required for each service library. The DirectConnect Server identifies the library by the file name. To install, load, or access a library, make sure that the executable file for that library exists in the server svclib subdirectory.

Service library configuration file

Each service library has a configuration collection. This file contains information for the service library and all of its services. The server defines the file format, but each configuration property is defined by the service library, regardless of whether the property is managed at the service library or the service level. The configuration files reside in the server cfg subdirectory.

For information on configuring service library properties, see the appropriate DirectConnect Access Service User's Guide for your database system.

Service Name Redirection file

The service name redirection file snrf.tbl is an optional file that contains all information necessary to redirect incoming service names to other services. The file resides in the server cfg subdirectory. For information on service name redirection, see Chapter 5, "Using service name redirection" .

Log file

The log file contains operational information that you can use to correct problems. This is the only active log file for the system. Although the file is maintained in U.S. English, any logged client messages appear in the client language. The log file resides in the server log subdirectory. For logging information, see Chapter 6, "Log and trace files" .

Trace file

The trace file provides debugging information for Sybase personnel. This file is the only active trace file for the system. You can turn it on and off through server configuration. Although the trace file is maintained in U.S. English, any logged client messages appear in the client language. The trace file resides in the log subdirectory. For tracing information, see Chapter 6, "Log and trace files" .