CERN Accelerating science

ATLAS Slides
Report number	ATL-DAQ-SLIDE-2016-766
Title	Master of Puppets
Author(s)	Ballestrero, Sergio (University of Johannesburg, Department of Physics) ; Brasolin, Franco (INFN Bologna and Universita' di Bologna, Dipartimento di Fisica e Astronomia) ; Fazio, Daniel (CERN) ; Gament, Costin-Eugen (University Politehnica Bucharest) ; Lee, Christopher (University of Cape Town) ; Scannicchio, Diana (University of California, Irvine) ; Twomey, Matthew Shaun (Department of Physics, University of Washington, Seattle)
Corporate author(s)	The ATLAS collaboration
Collaboration	ATLAS Collaboration
Submitted to	22nd International Conference on Computing in High Energy and Nuclear Physics, CHEP 2016, San Francisco, Usa, 10 - 14 Oct 2016
Submitted by	[email protected] on 04 Oct 2016
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Abstract	Within the ATLAS detector, the Trigger and Data Acquisition system is responsible for the online processing of data streamed from the detector during collisions at the Large Hadron Collider at CERN. The online farm is comprised of ~4000 servers processing the data read out from ~100 million detector channels through multiple trigger levels. Configuring of these servers is not an easy task, especially since the detector itself is made up of multiple different sub-detectors, each with their own particular requirements. The previous method of configuring these servers, using Quattor and a hierarchical scripts system was cumbersome and restrictive. A better, unified system was therefore required to simplify the tasks of the TDAQ Systems Administrators, for both the local and net booted systems, and to be able to fulfil the requirements of TDAQ, Detector Control Systems and the sub-detectors groups. Various configuration management systems were evaluated, though in the end, Puppet was chosen as the application of choice and was the first such implementation at CERN. In this paper we describe the newly implemented system, detailing the redesign, the configuration and the use of the Puppet manifests to ensure a sane state of the entire farm.