Speaker
Dr
Jose Antonio Coarasa Perez
(Department of Physics - Univ. of California at San Diego (UCSD) and CERN, Geneva, Switzerland)
Description
The CMS online cluster consists of more than 2000 computers, mostly under Scientific Linux CERN, running the 10000 applications instances responsible for the data acquisition and experiment control on a 24/7 basis.
The challenging dimension of the cluster constrained the design and implementation of the infrastructure:
- The critical nature of the control applications demands a tight security and independence of external networks, including the CERN's network, while maintaining a high availability of the services;
- The evolving nature of the acquisition applications requires an easy management and configuration infrastructure suitable for large scale installation and fast configuration turnaround: any failing computer can be replaced and fully configured automatically from scratch in less than 10 minutes; more than 1000 computers can be reinstalled concurrently in less than 60 minutes and the infrastructure is easily scalable to reduce the installation time and accommodate for more computers at the same time;
- The large number of subsystems and users imposes dealing with heterogeneous systems and services;
- In the next two years the cluster will increase its size more than 50% while the detector reaches its nominal capacity, which demands for easy scalability;
In this paper we will revise the tools and solutions used to fulfill the aforementioned requirements and others coming from the scale of the cluster. Details will be given on the problems and solutions adopted, ranging from the implementation of the redundant and load balanced network services (DNS, DHCP, LDAP, Kerberos, file serving, proxys...) to the configuration and deployment infrastructure based on quattor.
Primary author
Dr
Jose Antonio Coarasa Perez
(Department of Physics - Univ. of California at San Diego (UCSD) and CERN, Geneva, Switzerland)
Co-authors
Alexander Oh
(CERN, Geneva, Switzerland)
Andrea Petrucci
(University of California, San Diego, San Diego, California, USA)
Andreas Meyer
(DESY, Hamburg, Germany and CERN, Geneva, Switzerland)
Attila Racz
(CERN, Geneva, Switzerland)
Christian Deldicque
(CERN, Geneva, Switzerland)
Christoph Paus
(Massachusetts Institute of Technology, Cambridge, Massachusetts, USA)
Christoph Schwick
(CERN, Geneva, Switzerland)
Dennis Shpakov
(FNAL, Chicago, Illinois, USA)
Derek Hatton
(DESY, Hamburg, Germany)
Dominique Gigi
(CERN, Geneva, Switzerland)
Elizabeth Dusinberre
(University of California, San Diego, San Diego, California, USA)
Emilio Meschi
(CERN, Geneva, Switzerland)
Eric Cano
(CERN, Geneva, Switzerland)
Fabiana Fortes Rodrigues
(Centro Federal de Educação Tecnológica Celso Suckow da Fonseca, Rio de Janeiro , Brazil)
Frank Glege
(CERN, Geneva, Switzerland)
Frans Meijers
(CERN, Geneva, Switzerland)
Gerry Bauer
(Massachusetts Institute of Technology, Cambridge, Massachusetts, USA)
Hannes Sakulin
(CERN, Geneva, Switzerland)
Harry Cheung
(FNAL, Chicago, Illinois, USA)
James Branson
(University of California, San Diego, San Diego, California, USA)
Jean-Francois Laurens
(CERN, Geneva, Switzerland)
Joao Varela
(LIP, Lisbon, Portugal and CERN, Geneva, Switzerland)
Johannes Gutleber
(CERN, Geneva, Switzerland)
Juan Antonio Lopez Perez
(CERN, Geneva, Switzerland and FNAL, Chicago, Illinois, USA)
Konstanty Sumorok
(Massachusetts Institute of Technology, Cambridge, Massachusetts, USA)
Kurt Biery
(FNAL, Chicago, Illinois, USA)
Luciano Orsini
(CERN, Geneva, Switzerland)
Marco Pieri
(University of California, San Diego, San Diego, California, USA)
Marco Zanetti
(CERN, Geneva, Switzerland)
Marek Ciganek
(CERN, Geneva, Switzerland)
Matteo Sani
(University of California, San Diego, San Diego, California, USA)
Philipp Schieferdecker
(CERN, Geneva, Switzerland)
Remigius K Mommsen
(FNAL, Chicago, Illinois, USA)
Robert Gomez-Reino
(CERN, Geneva, Switzerland)
Roland Moser
(CERN, Geneva, Switzerland)
Samim Erhan
(CERN, Geneva, Switzerland and University of California, Los Angeles, Los Angeles, California, USA)
Sean Simon
(University of California, San Diego, San Diego, California, USA)
Sergio Cittolin
(CERN, Geneva, Switzerland)
Ulf Behrens
(DESY, Hamburg, Germany)
Vaios Patras
(CERN, Geneva, Switzerland)
Vivian O'Dell
(FNAL, Chicago, Illinois, USA)
