Short overview of the gLite Grid middleware

1. gLite Overview Leandro N. Ciuffo INFN-Catania (Italy) Grid User Tutorial Kampala - Uganda, 11.11.2008

2. Virtual Organizations (1/2) Virtual Organizations (VOs) Groups of users and resources with common research interests. They require tools / specific services that empowers collaborative work between its members, which are normally distributed geographically. gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 2

3. Virtual Organizations (2/2) gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 3

4. Basic concepts Computational resources: Physical machines on which users wants to run their programs (called "jobs") and store or access data files, without worrying about their physical location. Job: A computational task (an executable program or a script) that an user wants to run on the Grid, and get its results on his or her local workstation. Job Submission: Is the action of delegating on the Grid the identification and selection of the best computing resource to run a Job, and to manage its execution. gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 4

5. gLite-2 gLite-1 LCG-2 LCG-1 gLite-3 GTK2 Web services based GTK4 gLite Light middleware for Grid Computing Service Oriented Architecture (SOA) based Born from the joint effort of research and academic institutions members of the EGEE project gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 5

6. gLite services (1/2) 5 high-level services groups Grid access Security Information system Data management Job management gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 6

7. Available Pending gLite services (2/2) gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 7

8. Components and architecture (1/3) UI WMS LB VOMS BDII CE WN SE LFC AMGA User Interface Workload management system Logging and bookkeeping service Virtual Organization Management service Information system Computing element Worker nodes Storage element File catalog Metadata catalog gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 8

9. Components and architecture (2/3) The User Interface (UI) is the Grid entry point. It's considered part of the Workload Management System (WMS) The Workload Management System (WMS) is a set of components which are in charge of finding the best resource among the available Computing Elements, which fulfills user job requirements, and managing its execution transparently The Computing element (CE) is the computational resource.Is the entry point to the cluster's queue management system (TORQUE, PBS, LSF, CONDOR)‏ The Worker Nodesare the machines where jobs are actually executed. They are connected to the CE trough the local queue management system, where jobs are queued for their execution gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 9

10. Components and architecture (3/3) The Information System (BDII), keeps information about available resources and their status, and the general status of the whole system. The Logging and bookkeeping service(LB), is in charge of keeping track of jobs events that occurs during their execution. The Virtual Organization Management service (VOMS), provides authentication and authorization mechanisms to grant access to resources. The Storage element (SE)andFile catalog (LFC), manages storage and transfer services of big files, and facilitates availability and localization of data files required by user's jobs. TheMetadata Catalog (AMGA), allows transparent storage and retrieval of metadata about data files or jobs, or general purpose information (distributed database)‏ gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 10

11. SE BDII LFC SE Interaction among components LB User Interface Worker nodes VOMS CE ssh Worker nodes WMS Worker nodes CE Worker nodes AMGA gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 11

12. Core Services Grid site A Grid “core services” SE VOMS(VO1) BDII LFC CE+ WNs AMGA GIIS UI VOMS(VO2) WMS+LB GIIS Grid site C AMGA UI Central UI GIIS CE+ WNs SE SE Grid site B CE+ WNs gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 12

13. gLite Information System Berkeley Database Information Index (BDII)‏ Information is hierarchically stored under a tree-based model (LDAP implementation of the GLUE schema)‏ GRISResource level information GIISSite level information BDIIVO level information VO Level Site Level ResourceLevel gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 13

14. A job's life cycle CE UI WMS gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 14

15. Core Services - GILDA https://gilda.ct.infn.it/testbed.html gLiteoverview – Short Grid User Tutorial, Kampala, 11/11/2009 15

16. Questions