Difference between revisions of "Administrator's Guide: Introduction"

Revision as of 13:11, 29 November 2007

Overview

Welcome to the gCube's Administrators Guide. The purpose of this document is to provide instructions regarding the initial installation and configuration, management and daily administration of a grid infrastructure based on the gCube system. gCube is a versatile, rich featured grid platform that has been developed in the context of the DILIGENT European IST research project [ref].

The platform follows the Service Oriented paradigm and exploits and extends various existing grid middlewares and collaborative tools like the Globus Toolkit 4 [ref], gLite [ref], the Gridsphere Portals framework, etc[ref]. gCube offers a feature full platform for distributed hosting, management and retrieval of data and information, and a framework for extending state-of-the-art indexing, selection, fusion, extraction, description, annotation, transformation, and presentation of content.

gCube Architecture

gCube enables scientists to declaratively and dynamically build transient Virtual Research Environments --VREs-- by aggregating and deploying on-demand content resources, application services, and computing resources. It also monitors the shared resources during the VREs lifetime guaranteeing their optimal allocation and exploitation. Finally, it provides mechanisms to easily create VREs dedicated web portals through which scientists can access their content and services. The gCube system is realised as a service oriented framework composed of a set of interacting services providing:

• support for the creation and operation of on-demand, transient virtual research environment;
• features necessary for handling shared content and application resources;
• access to information sources and applications provided by third-parties;
• a set of typical DL functions, like search, annotation, personalisation, document visualisation.

These services are designed to exploit the gLite middleware and are capable to consume the high computational and storage capabilities of the Grid infrastructure released by the EGEE [ref] project. Thus gCube services support complex and time consuming functionalities, while focusing on optimizing resource usage and satisfying QoS contracts

From the logical point of view, the gCube system is organised according the following layers:

Collective Layer

The Collective Layer enhances existing Grid collective services with the functionalities able to support the complex services interactions required by the Digital Library Layer. The Collective Layer contains services that are not associated with any one specific resource but rather are global in nature and manage interactions across collections of resources.

Digital Library Layer

The Digital Library Layer selects, integrates and enhances a set of reliable and dependable production-quality services, developed in digital library projects and applications, in order to cover the fundamental functionalities required for any virtual research environment in the e-knowledge area. The services of this layer provide submission, indexing and discovery of mixed-media objects (documents, videos, images, environmental data, etc.), and the management and processing of these objects through annotation, composition, cooperative editing, etc. It also supports the dynamic creation and access to transient virtual research environment.

Application Specific Layer

The Application-Specific Layer contains application specific services. Third party providers are enabled to migrate their data or functional components to the gCube framework. Specifications are being produced that facilitate the plug-in of legacy components needed to support user-specific scenarios and enable the re-use of existing content and applications.

The current manual focuses mainly on the Collection Layer components which are the cornerstone of any gCube installation. The rest of the components are either deployed dynamically from the Keeper service or are application/user community specific (for instance the end user Portals)

Intended Readership

This manual targets system administrators and people responsible for setting up a gCube based Grid environment. It assumes fluency in Linux-based usage and administration, and knowledge of Globus Toolkit 4 Java WS-Core inner details. Since, some components take advantage of the gLite middleware, experience in setting up gLite-based grid infrastructures would be useful. Finally, as with all grid platform, also in gCube security plays a paramount role in the architecture. Both system administrator's and end users should be familiar with concepts like, digital certificates, certification authorities, authorization & authentication, etc.

Being a mosaic of different services and tools makes the installation of a new gCube infrastructure and the initialization of a Digital Library can be a daunting process. This guide covers the basic steps of the core components installation like the DHN and Collective Layer services, provides an overview picture of the gCube architecture with emphasis to its security characteristics.

Related Documents

Apart from the Administrators Guide, DILIGENT has also made available two additional support documents:

• the User's Guide, which provides usage information and guidelines for the end-user of the two user communities that currently exploit the platform, namely ImpECt and ARTE.
• the Developer's Guide, which target application programmers that they want to reuse and extend the rich Service Oriented, grid API, provided by gCube.

Additional material that will help system administrators is the

• gLite 3.0 Administrators Guide [provide link]
• Globus Toolkit 4 Administrators Guide

Regarding the architecture and inner details of gCube, the interested reader can visit the official gCube platform web site [1].

Lexical Abbreviations

The following abbreviations are used extensively throughout the document:

Problem Reporting

For problem reporting or any other enquiries regarding this document please contact Vangelis Floros (floros(AT)di.uoa.gr).