Distributed TREX Systems (Multiple Host Installation) 

Purpose

Search and Classification (TREX) consists of a client component and a server component. The server component is based on a flexible architecture that allows a distributed installation. A distributed system has the following advantages:

●      Load balancing

You can distribute the search and indexing load among several hosts.

●      High Availability

You can make searching and indexing highly available.

This guide explains how to plan and implement a distributed system. It is aimed at technology consultants.

The guide is structured as follows:

●      Naming Conventions contains information on the naming conventions used in this guide.

●      Required Documentation lists the documentation that you need to implement a distributed system.

●      TREX Fundamentals contains information on the TREX architecture and basic information on distributed systems. You need this information to plan a distributed system. Read this information before you begin to implement your distributed system.

●      Setting Up a Distributed System and Delta Index and Index Replication Configuration describe how to implement a distributed system.

●      Changing a Distributed System describes changes that you can make to your system after the installation.

●      Distributed Preprocessing of Documents describes how to distribute the preprocessing of documents among several hosts. This section is relevant if you want to index documents whose preprocessing takes up a lot of time and system resources. This can be the case if you want to index large PDF files.

●      The appendix contains information on stopping and starting a distributed system. It also contains information on starting the TREX admin tool and changing the queue parameters and the Java client parameters. 

Restricted support for the global file system function for TREX 7.1.

TREX 7.0 allows you to install a central TREX instance on a global file system. On a global file system, you can store files for the SAP profiles centrally so that other TREX dialog instances can access them. You can use this function to set up distributed TREX landscapes. TREX 7.1 currently does not support the global file system function.

In the TREX 7.1 installation, the global file system function is available in restricted form only. The customer can no longer specify the path to the global file system during the installation process (SAP system directory usr/sap/<sid>/sys). The global file system is installed once only, on the host on which you initially install TREX 7.1 and it cannot be installed again independent of this. Therefore, there is still a global file system in the TREX 7.1 installation, but it cannot be installed on another host in the TREX landscape independent of the initial TREX 7.1 installation. TREX is developing the unrestricted global file system feature in TREX 7.1 for the end of 2008.