Abstract
The DataTAG project has contributed to the creation of the middleware distribution constituting the base of the LCG-0 pilot. This distribution has demonstrated the possibility of building an EDG release based on iVDGL/VDT, integrating the GLUE schema and early components of the EDG middleware.
On February 28th 2003, the LCG Grid Deployment
Group has announced the availability of the first release of the
LCG-0 Pilot software to be used by LCG early deployment sites in
order to start building the LCG infrastructure and exercise the
Grid deployment process.
This release of the software has also been used to test the
feasibility of a middleware based on components coming from the
iVDGL-VDT distribution and from the EDG middleware and it runs on
Linux RedHat 7.3 with version 2.95.2 of the gcc compiler.
The great experience gained during the effort of setting up the
WorldGrid testbed together with the American companion project
iVDGL, to test interoperability solutions between two different
Grid Infrastructures such as EDG and iVDGL/VDT and the success of
the demonstrations carried out at IST2002 in Copenhagen and
SuperComputing 2002 in Baltimore, has allowed DataTAG to lead the
effort of creating the middleware distribution constituting the
base of LCG-0 Pilot.
During the week of January 20th 2003, 5 people from the DataTAG
WP4 Interoperability Team have met at CERN together with
representatives of the VDT team to work closely with the LCG
Deployment Group in order to provide a middleware solution which
integrates most of the features already experimented with in the
WorldGrid testbed, together with some early integration of new
components part of the EDG release 2.0 due to come by the end of
April 2003.
Among the features supported by the LCG-0 Pilot, the middleware
integrates the first release of the
GLUE schema.
Through this schema Grid resources, their status and monitoring
information are published to the Information Service for use by the
matchmaking mechanism of the EDG Resource Broker, the monitoring
systems and end-user applications. DataTAG WP4 has participated in
the effort of defining common resource schema together with iVDGL
in the context of the GLUE program. At CERN the DataTAG WP4 team
has extended the default schema included in VDT to include new
descriptions needed for the new edt-monitor monitoring package
based on Nagios.
The EDG 1.4
Resource Broker has also been modified
to make it GLUE-schema aware. EDG will adopt the GLUE schema with
the new release of the software due at the end of April 2003. The
experience gained exercising the matchmaking mechanism of this
release of the Resource Broker that takes advantage of the new GLUE
schema will be fed back to EDG for the future release.
Together with the Resource Broker, another component of the
EDG WorkLoad Management has been readapted: the
Job
Description Language (JDL). Through the new JDL, more
possibilities are given to the user to specify Requirements that
need to be satisfied in order for the job to run correctly.
The DataTAG version of the EDG
Data Management Tools
contains support for the old Globus Replica Management Tools as
well as for the new Replica Location Service, designed in a joint
project by EDG and Globus. This new interface has allowed the LCG
Grid Deployment Group to exercise those components before the
deployment in EDG, execute stress tests and find potential problems
for a production environment.
DataTAG is also participating in a joint project with LCG for the
design and implementation of a new
Grid monitoring
tool based on Nagios to identify deployment problems and
general Grid malfunctioning sites or components. Such tools should
be used at operation centers for problems spotting. The edt-monitor
tool will be deployed on LCG-0 Pilot only for testing purposes. A
production release will be available for the LCG-1 Prototype
Service.
DataTAG is planning on demonstrating the functionality provided by
the LCG-0 release together with an early integration of the Virtual
Organization Management Services (VOMS) at the first project review
that has taken place the 19th of March 2003.
For more information on the DataTAG project see:
http://www.datatag.org
For more information on the DataTAG/WorldGrid
project see:
http://datatag-demo.pi.infn.it
Other references:
http://lcg.web.cern.ch
http://eu-datagrid.web.cern.ch
http://www.ivdgl.org
The complete list of authors of this article,
participating in the DataTAG project is:
Flavia Donno(1), Sergio
Andreozzi(5),
Vincenzo Ciaschini(5),
Sergio Fantinel(2),
David Rebatto(3),
Elisabetta Ronchieri(6), Gennaro
Tortone(4),
Luca Vaccarossa(3),
Marco Verlato(2),
Cristina Vistoli(5)
(1) CERN, IT/GD, (2) DataTAG, INFN Padova, (3) DataTAG, INFN Milano,
(4) DataTAG, INFN Napoli, (5) DataTAG, CNAF Bologna, (6) DataGrid, CNAF
Bologna
About the author(s):
Flavia Donno is Section Leader of the Experiment Integration and Support team in the IT Grid Deployment Group