Speaker
Dr
Jose Antonio Coarasa Perez
(CERN)
Description
The CMS online cluster consists of more than 3000 computers. It has been exclusively used for the Data Acquisition of the CMS experiment at CERN, archiving around 20Tbytes of data per day.
An openstack cloud layer has been deployed on part of the cluster (totalling more than 13000 cores) as a minimal overlay so as to leave the primary role of the computers untouched while allowing an opportunistic usage of the cluster. This allows running offline computing jobs on the online infrastructure while it is not (fully) used.
We will present the architectural choices made to deploy an unusual, as opposed to dedicated, "overlaid cloud infrastructure". These architectural choices ensured a minimal impact on the running cluster configuration while giving a maximal segregation of the overlaid virtual computer infrastructure. Openvswitch was chosen during the proof of concept phase in order to avoid changes on the network infrastructure. Its use will be illustrated as well as the final networking configuration used. The design and performance of the openstack cloud controlling layer will be also presented together with new developments and experience from the first year of usage.
Primary author
Dr
Jose Antonio Coarasa Perez
(CERN)
Co-authors
Andre Georg Holzner
Andrea Petrucci
(CERN)
Andrei Cristian Spataru
(CERN)
Dr
Attila Racz
(CERN)
Aymeric Arnaud Dupont
(CERN)
Carlos Nunez Barranco Fernandez
(CERN)
Christian Deldicque
(CERN)
Christian Hartl
(CERN)
Christoph Paus
(Massachusetts Inst. of Technology (US))
Christoph Schwick
(CERN)
Christopher Colin Wakefield
(Staffordshire University (GB))
Dominique Gigi
(CERN)
Emilio Meschi
(CERN)
Fabian Stoeckli
(Massachusetts Inst. of Technology (US))
Frank Glege
(CERN)
Frans Meijers
(CERN)
Gerry Bauer
(Massachusetts Inst. of Technology (US))
Dr
Giovanni Polese
(University of Wisconsin (US))
Hannes Sakulin
(CERN)
James Gordon Branson
(Univ. of California San Diego (US))
Konstanty Sumorok
(Massachusetts Inst. of Technology (US))
Lorenzo Masetti
(CERN)
Luciano Orsini
(CERN)
Dr
Marc Dobson
(CERN)
Marco Pieri
(Univ. of California San Diego (US))
Matteo Sani
(Univ. of California San Diego (US))
Olivier Chaze
(CERN)
Olivier Raginel
(Massachusetts Inst. of Technology (US))
Petr Zejdl
(CERN)
Dr
Remi Mommsen
(Fermi National Accelerator Lab. (US))
Robert Gomez-Reino Garrido
(CERN)
Samim Erhan
(Univ. of California Los Angeles (US))
Sergio Cittolin
(Univ. of California San Diego (US))
Srecko Morovic
(Institute Rudjer Boskovic (HR))
Ulf Behrens
(Deutsches Elektronen-Synchrotron (DE))
Vivian O'Dell
(Fermi National Accelerator Laboratory (FNAL))
Wojciech Andrzej Ozga
(AGH University of Science and Technology (PL))
