Status of AliEn2 Services ALICE offline week Latchezar Betev Geneva, June 01, 2005

2 AliEn site services 01 June 2005 Outline  Services  Installation  ALICE Grid for PDC’05

3 AliEn site services 01 June 2005 AliEn2 services Local scheduler ALICE VO – central services Central Task Queue Job submission File Catalogue Configuration Accounting User authentication Computing Element Workload management Job Monitoring Storage Element(s) DB Data Transfer Storage Element Cluster Monitor AliEn Site services Disk and MSS Existing site components ALICE VO – Site services integration

4 AliEn site services 01 June 2005 AliEn2 services (2)  PackMan – application software delivery (ROOT, AliRoot, …):  Central and site service VO User  User/global application software management

5 AliEn site services 01 June 2005 AliEn services (3)  PackMan:  Managed package dependencies:  AliRoot 4.02.Rev.01 depends on ROOT – will trigger installation of ROOT  Automatic installation through declarations  xrootd – data transfer protocol:  Performing file transport system, descendant of rootd (but now completely reworked), xrootd client is ROOT/posix compliant  Load-balancing, scalability, speed  Replaces AliEn aiod as file transfer mechanism  More information at  MonALISA – monitoring:  Central repository, site agents  ApMon clients, embedded in the job wrapper:  Communication through UDP

6 AliEn site services 01 June 2005 AliEn Services (4)  Many new repository features  Interactive map with a lot of ‘at-glance’ information  Site agents repository – data filtering and averaging  A de-facto standard for Grid3 (US)

7 AliEn site services 01 June 2005 AliEn installation  New intuitive interactive alien-installer:

8 AliEn site services 01 June 2005 AliEn installation (2)  Very robust – carries all dependencies, able to install itself  Services of AliEn are partitioned by location  Supports software updates

9 AliEn site services 01 June 2005 AliEn installation (3)  When everything works the installation is extremely easy and straightforward  After installation: additional tuning of site parameters:  Storage, local scheduler, network ports, etc…

10 AliEn site services 01 June 2005 HP ProLiant DL580 AliEn central services HP ProLiant DL360 AliEn to CASTOR (MSS) interface HP ProLiant DL380 gShell API service Disk SE log files storage 1TB SATA Disk server AliEn services at CERN

11 AliEn site services 01 June 2005 AliEn services at CERN(2)  Central AliEn services – support by offline, running on our resources  IT support:  Storage capacities: 3 CASTOR disk stagers (50 TB)  CE, PackMan, SE load balancer for xrootd: lxgate06  Data transport slave servers: castorgrid01 to castorgrid08  Lxbatch capacity – 150 shares (approx 200 jobs)

12 AliEn site services 01 June 2005 AliEn services at computing centres  Identical as last year:  User account on a head node (or dedicated host) – this model is now being adopted by the other LHC experiments  Support by local expert is very important  Currently installed sites: Patricia Lorenzo (IT) Chang Choi Claudiu Schiaua (Bucharest) Jan Fiete (Muenster) Kilian Schwarz (Karlsruhe)

13 AliEn site services 01 June 2005 ALICE Grid for PDC’05  Comoputing centres (ALICE resources): 30  CERN  France: Lyon, Clermont-Ferrand, Nantes  Germany: GridKa, GSI, IKP Muenster  Italy: CNAF, Catania, Bari, Torino, Padova  UK: RAL  Holland: NIKHEF  Nordic facility: NDGF  US: OSC, NERSC, Houston  South Africa: Cape Town  Russia: IHEP, ITEP, KI, JINR, SPbSU, SINP  Romania: NIPNE  India: VECC  Slovakia: IEP  Czech Republic: Prague  South Korea: Sejong

14 AliEn site services 01 June 2005 ALICE Grid for PDC’05  30 Centres  Wealth of resources (2005): ~1700 CPUs, 250 TB disk (not counting CERN)  All these have to be ‘glued’ together by the Grid middleware  In 2004 we managed to run on 17 sites with AliEn (+LCG resources through interface)  This year we should do better  In 2006, the amount of available resources will double, as well as the volume of the computing exercise (PDC’06)

15 AliEn site services 01 June 2005 Current status and problems  Installation of sites ongoing:  With the help from the site experts  Also building up local expert group - to be able to support the running of the ALICE Grid in a 24/7 regime  List of problems:  The AliEn2 software is new (with respect to AliEn):  There are problems which only appear when the software is tested in a real environment and with complex tasks  We need time to learn how to operate it in a ‘production’ mode  The initial setup procedure is relatively slow:  We have done it before  We do need to push through this phase to be able to do the production and analysis of the ALICE data  The functionality expectations are very high

16 AliEn site services 01 June 2005 Development team  Experts, who provide all our Grid software and support for its functioning:  AliEn: Predrag Buncic, Pablo Saiz  ARDA: Andreas Peters, Derek Feichtinger, Catalin Cirstoiu, Slavomir Biegluk