SAP Basis - NW Architecture

SAP NetWeaver is one of the central components of the entire SAP software stack and provides you a platform for other components and JAVA and ABAP applications.

SAP Application server consists of multiple application server instances and also database servers. With use of dialog instance, it also contains message server and an enqueue server.

The following is a dialog instance executed by a user −

These are the different components of the Dialog Instance −

Internal Communication Manager − This is used to process both client and server web requests. It supports protocol – HTTP, HTTPS, SMTP.

Dispatcher − This is used to distribute the user request to different work processes. If all the work processes are busy, requests are stored in the dispatcher queue.

Work Processes − These are used to execute Java or ABAP programs.

SAP Gateway − This provides RFC interface between SAP instances.

Message Server − This is used for message communication and also balances the load in SAP system.

Installation Options for SAP NetWeaver

SAP NetWeaver provides the following installation options −

• ABAP System − This comes with an integrated VM Container. With this installation, you can run ABAP programs and selected SAP Java applications (shown in left box).

• Java System − The components to the right in the above image constitute the Java System. With the installation of this, you can run J2EE applications but not any ABAP programs.

• ABAP + Java system − All the components shown in the above image constitute the ABAP + Java System.

Application Center and Instances

The SAP NetWeaver work center includes the configuration of the following tools −

Adobe Document Services − This allows you to register the Adobe Reader Rights credentials as well as keep track of all unlicensed interactive form designs in your system.

Application Module − This allows you to view the details of the deployed applications and their modules. Here, you can also perform the run-time configuration of the application modules.

Application Resources − This allows you to enable applications to make use of external resources. A NW Administrator can add or delete the application resources.

Authentication and Single Sign-On − This allows you to choose the required authentication mechanism for your applications. You can configure the following authentication and SSO −

• AS Java as a Service Provider
• Kerberos

Certificates and Keys − This allows you to manage the AS Java certificates and keys.

Composite Application Framework Authorization Tool − This allows you to manage business rules and Instance Level Permissions for CAF applications, business object nodes and AS Java instances.

Configuration Wizard − You can make technical settings required for the technical processing of a system or a technical scenario.

Destinations − This can be used to specify the remote service's address and the user authentication information for remote connections.

Development Infrastructur − This is required while developing with Java and you want to manage it with Transport Management System (TMS).

Identity Management − This allows you as an administrator to control applications access by creating users and providing these users with a means of authenticating themselves to an application.

Internationalization − This allows you to manage data from double stack systems and also used for synchronization purpose.

Java HTTP Provider Configuration − You can create new virtual hosts and configure existing ones for all registered systems.

Java Class Loader Viewer − You can monitor the hierarchy and references between the class loaders in the AS Java.

Java System Properties − Using this, you can view current system configuration of Application server JAVA and you can edit the properties that are marked as online modifiable.

Java Connection JCo RFC Provider − You can manage the Java Connector Remote Function Call (JCo RFC) Destinations. This allows you to create, edit and view existing connections.

JMS Server Configuration − This is used to create new JMS resources.

Licenses − You can request and install new SAP licenses.

Log Configuration − You can view current log configuration, change security or reset it to default.

Message Server − You can monitor message server parameters and settings.

SAP NetWeaver Administrator Tool − SAP NetWeaver Administrator (NWA) is a web-based tool that allows you to perform configuration, advanced administration, and also to monitor, troubleshoot, and diagnose a SAP NetWeaver system.

You can use NWA tool in the following working modes −

• Online
• Local and remote

Managing Java Instances using NWA

Follow these steps to change the status of Java instances at runtime.

Step 1 − Go to SAP NetWeaver Administrator > Operations > Systems > Start & Stop

Step 2 − Now, go to Java Instances tab under NWA.

Step 3 − You can see all available instances with corresponding information about the server processes within the instance.

Step 4 − Select an instance to perform the following functions under NWA −

• Start, stop or restart a Java instance.
• Enable or disable debug mode for AS Java processes.
• View and refresh OS processes.
• Clear the DNS cache for a particular instance.
• Set a number of server processes (nodes).

SAP NW System Landscape

Follow these steps to perform the implementation of SAP NetWeaver system −

Step 1 − Plan the implementation by defining the scope, hardware and software requirements, and release instructions.

Step 2 − Define the system landscape for the use cases.

Step 3 − Install the components of SAP NetWeaver system.

Step 4 − Configure SAP NW systems.

System Landscape Management using SAP Solution Manager

SAP recommends the use of the latest version of the SAP Solution Manager to manage your system landscape. You can download the latest version from SAP Support Portal http://support.sap.com/solutionmanager

It is important to correctly define your SAP system landscape in the following versions of SAP Solution Manager to maintain it correctly.

SAP Solution Manager 7.0

You can use the SAP Solution Manager System Landscape transaction code — SMSY for the complete system description.

SAP Solution Manager 7.1 SP01 to SP04

You can use the Landscape Management Database transaction code — LMDB to maintain technical system information. To maintain logical product information, you can use the transaction code — SMSY.

SAP Solution Manager 7.1 SP05 and higher

You can use the Landscape Management Database transaction code — LMDB for the complete system description and in this, transaction code — SMSY is no longer required.

Verifying Landscape with SAP Solution Manager

To verify and correct your system landscape, SAP recommends that you use the verification functions of the following versions of SAP Solution Manager.

SAP Solution Manager 7.0 to 7.1 SP04

Use Landscape Verification 1.0 for SAP Solution Manager. This add-on allows you to identify and correct issues in your SAP Solution Manager landscape (Transaction SMSY) before they cause problems, for example, during a system update. Example for errors are a missing connection to the System Landscape Directory or the incorrect assignment of products to technical systems. For each type of error, a generic description for the solution is provided.

SAP Solution Manager 7.1 SP05 or higher

Use the landscape verification function that is embedded into the product system editor of the Landscape Management Database (LMDB). It replaces the previous Landscape Verification tool.