GT 4.0: Information Services

Abstract

The Monitoring and Discovery System (MDS) is a suite of web services to monitor and discover resources and services on Grids. This system allows users to discover what resources are considered part of a Virtual Organization (VO) and to monitor those resources. MDS services provide query and subscription interfaces to arbitrarily detailed resource data and a trigger interface that can be configured to take action when pre-configured trouble conditions are met.

For more information about the information services concepts behind GT4, see Information Service: Key Concepts.

GT4’s MDS includes:

  • WS MDS, the WSRF implementation of MDS, which consists of:
    • Index Service [pdf] - collects monitoring and discovery information from Grid resources, and publishes it in a single location.
    • Trigger Service [pdf] - collects data from resources on the grid and, if administrator defined rules match, can perform various actions.
    • Aggregator Framework [pdf] - the software framework on which the above WS MDS services are built.
    • WebMDS [pdf] - enables end users to view monitoring information via a standard web browser interface, without installing any additional software on their PC.
    • UsefulRP (4.0.5+ only) - extensible software component that can be used to dynamically generate XML values for one or more WSRF Resource Properties in any given GT4 Java WSRF-Core compatible service.
    • Information Providers (4.0.5+ only) - used to gather information either via execution aggregator sources (in the Aggregator Framework) or via UsefulRP.
  • Pre-WS MDS [pdf] (now deprecated) - the MDS implementation first introduced in GT2.