Understanding the SAP NetWeaver BW Accelerator

This chapter download explains the basics of the SAP NetWeaver BW Accelerator and how to repair connections to the NetWeaver BW system.

SAP NetWeaver BI Accelerator

SAP NetWeaver BI Accelerator
Chapter 5: Advanced Administration

A Practical Guide to SAP NetWeaver Business Warehouse (BW) 7.0, Ch. 1

The NetWeaver BI Accelerator, (now called the NetWeaver BW Accelerator), is an external plug-in appliance for NetWeaver BW, designed to enhance the performance of analytics processing. The BWA itself is licensed per blade server, and the accelerator is powered by the TREX standalone administration tool. The TREX tool itself can display enough system information that users with sufficient experience can face numerous TREX-related challenges that arise during a BIA installation.

In this book excerpt from SAP NetWeaver BI Accelerator by J. Andre Ross (SAP Press, 2008), gain an overall understanding of how to configure the SAP NetWeaver BW Accelerator, and find out how to repair connections to the NetWeaver BW system. Get tips on how to perform NetWeaver BW optimization tasks, such as landscape reorganization, performance checks and adjusting indexing parameters. Moreover, gain further insight into how the TREX administration tool powers the BW Accelerator, and why only experienced NetWeaver administrators should handle the tool.

SAP NetWeaver BI Accelerator, Chapter 5:

Table of contents:
Understanding the SAP NetWeaver BW Accelerator
Performing RFC connection checks in NetWeaver BW with SAP TREX
Changing InfoCube metadata in SAP BW Accelerator

5 Advanced Administration

The administration tasks described so far have been part of the required skill set for any administrator of an SAP NetWeaver BI system with a BI accelerator attached. The tasks described in this section are more advanced and require additional skill to perform safely.

For users with sufficient experience, the TREX standalone administration tool offers a wealth of opportunities for deeper technical interaction with the TREX software within the accelerator. If a company requires SAP help to manage issues with its accelerator installation, an administrator can grant SAP service engineers remote access through the company firewall to the accelerator blades and thus allow them to use the TREX standalone administration tool over the Internet.

Section 5.1 introduces the TREX standalone administration tool. Section 5.2 describes some exceptional tasks such as repairing the connection to the BI system, checking and repairing the indexes, and performing a recovery. Section 5.3 describes some optimization tasks, including landscape reorganization, performance checks, and adjusting indexing parameters. Section 5.4 describes some tasks related to any necessary collaboration with SAP service experts, such as setting up a service connection, checking the BIA landscape, and creating trace files. Section 5.5 summarizes the chapter.

5.1 The TREX Standalone Administration Tool

This excerpt from SAP NetWeaver BI Accelerator by J. Andrew Ross is reprinted here with permission from SAP Press; Copyright 2008.

Download a pdf of this chapter.

 For fully detailed interaction with the TREX engine at the heart of the SAP NetWeaver BI Accelerator, there is no better tool than the TREX standalone administration tool. This is a graphical tool supporting point-and-click and drag-and-drop interaction. Most administrative tasks can be handled through the SAP Transactions RSDDBIAMON and TREXADMIN, but some more advanced tasks require use of the TREX standalone administration tool. This tool was built by and for TREX developers, to enable them to work more easily with their own growing creation, and for this reason it offers powerful features that can be dangerous in the hands of a beginner. The tool does not include the safeguards that a beginner might expect, and therefore it should not be made accessible to anyone who is not qualified to use it safely.

The TREX standalone administration tool supports a huge range of interactions and can display enough system information to enable technical experts to do whatever may be necessary to resolve any TREX issues that can arise in a productive BIA installation. If remote access to the tool is granted, SAP service engineers can use it to perform any troubleshooting task in TREX.

To start the TREX standalone administration tool:


  1. Open a command-line window on one of the BIA hosts.
  2. Change to user adm.
  3. Go to directory /usr/sap/ /TRX /.
  4. Execute command TREXAdmin.sh.

The default host on which to start the tool is the BIA blade hosting the active master name server. This is normally the first blade numerically in the set of BIA blades because the installation automatically assigns consecutive numbers to the blades, and the default master starts on the first blade. However, the tool can be started from any blade in the landscape and display the same information.

The TREX standalone administration tool opens at the view displayed when it was last closed. However, the natural view to display first is the Summary view (see Figure 5.1). The Status line above the Status Details panel tells you what you need to know first. In this case, all the alert icons are green (square). Above the Status line are some version and platform details, and the Status Details panel displays the more major check results such as memory consumption, number and total size of indexes, and whether traces are on or off.

After the Summary view, the first view to check in the TREX administration tool is perhaps the Services view (see Figure 5.2). All the main services on all the hosts in the landscape are listed. In this case, there are four blades in the landscape, and on each blade, there are name server, index server, RFC server, and "other" (alert server) services running. The green (square) icons down the left side show that all the services have status OK. The bars toward the center show that at the time of this screen capture, there is very little CPU activity or memory consumption on the blades.

TREX Admin Tool, Summary
Figure 5.1: TREX Admin Tool, Summary

TREX Admin Tool, Services
Figure 5.2: TREX Admin Tool, Services

To configure the BIA landscape, choose the Configuration view (see Figure 5.3).

The Scenario panel at the upper left enables you to select usage of backup index servers (the other options are inapplicable for the accelerator).

TREX Admin Tool, Configuration
Figure 5.3: TREX Admin Tool, Configuration

In the Scenario Details panel toward the right, the Backup tab offers a dropdown menu for selecting a backup mode. The available modes are:


  • shared (one backup for all masters)
  • dedicated (one backup for each master)
  • multiplexed (one backup for several masters)
  • mutual (each master is backup for another master)

The Index tab enables you to change the size threshold for splitting a large BIA index.

Below the tabs, the Hosts panel includes more detailed information and indicates with an asterisk which blade hosts the currently active master name server. Use of the word "slave" is an inheritance from the text search world and has no meaning for the accelerator.

Instead of configuring the alert server via Transaction TREXADMIN, you can do so from the TREX standalone administration tool by selecting the Alerts view, and then choosing Alert Server Configuration (see Figure 5.4). Both these alternatives offer the same functional capabilities.

In the top panel of the configuration dialog box, you can enter an e-mail address to which alerts above the given threshold (trace level) should be sent. In the middle panel, you can override the default set of checks that run regularly, at times specified by the code in the middle column, and you can change how often they run by editing the displayed cron job specification (for which there is a nearby Crontab Help button in case you forget the format). In the bottom panel, you can change the selection of individual checks that run in the selected check set.

TREX Admin Tool, Alert Server Configuration
Figure 5.4: TREX Admin Tool, Alert Server Configuration

You should ensure that the BIA blades can reach the SMTP server you specify as the destination for e-mail alert messages. Each TREX installation runs its own alert server, and the results from the checks run by each of the alert server processes are consolidated on the blade that hosts the active master name server so the active master sends the alert messages, but this can only succeed if TREX can access the SMTP server.

You can download a pdf of this chapter. You can also visit SAP Press to purchase a copy of SAP NetWeaver BI Accelerator.

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