1. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 0 Lezione 8 - 15 Dicembre 2009 Il materiale didattico usato in questo corso è stato mutuato da quello utilizzato da Paolo Veronesi per il corso di Griglie Computazionali per la Laurea Specialistica in Informatica tenuto nellanno accademico 2008/09 presso lUniversità degli Studi di Ferrara. Paolo Veronesi paolo.veronesi@cnaf.infn.it paolo.veronesi@cnaf.infn.it, pveronesi@unife.it http://www.cnaf.infn.it/~pveronesi/unife/ Università degli Studi di Bari – Corso di Laurea Specialistica in Informatica Tecnologia dei Servizi Grid e cloud computing A.A. 2009/2010 Giorgio Pietro Maggi giorgio.maggi@ba.infn.it, http://www.ba.infn.it/~maggi giorgio.maggi@ba.infn.it

2. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 1 Todays focus: Information Services Security Cross-organizational users Trust nobody Authorized access only Security Cross-organizational users Trust nobody Authorized access only Information Services Registry Notification Logging/auditing Information Services Registry Notification Logging/auditing Execution Management Job description & submission Scheduling Resource provisioning Execution Management Job description & submission Scheduling Resource provisioning Data Services Common access facilities Efficient & reliable transport Replication services Data Services Common access facilities Efficient & reliable transport Replication services Self-Management Self-configuration Self-optimization Self-healing Self-Management Self-configuration Self-optimization Self-healing Resource Management Discovery Monitoring Control Resource Management Discovery Monitoring Control OGSA OGSA profiles Web services foundation DONE

3. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 2 Outline What is the Information System Data Model: the GLUE Schema Overview Core entities OpenLDAP server introduction LCG Information Service Architecture Top BDII and Site BDII Information upgrade process

4. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 3 Information System What is? System to collect information on the state of resources Why? To discover resources of the grid and their nature To have useful data that helps who is in charge of managing the workload to do it more efficiently. To check for health status of resources. How? Monitoring state of resources locally and publishing right information on the information system. Adopting a data model that MUST be well known to all components that want to access monitored information Using different approaches that we are going to investigate in next slides

5. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 4 Design of Information Systems About Measures Measures SHOULD be sensitive to the aim the users want to achieve. Measures SHOULD be enough accurate to be considered valid. Rate of taking measures MUST be adequate to be used. About the gathering of Information How and when collected info should be published? Where should collected info be stored? How long should this info be maintained in the storage? Querying the Information System Where should queries be sent to have a response? What syntax and protocols have to be adopted to make queries? What is the adopted data model to describe resources? Security Who is allowed to execute queries against the IS and what type of queries is he allowed to do? Management of user rights and credentials.

6. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 5 Adopted Information Systems The BDII (Berkley DB Information Index) has been adopted in LCG middleware as the Information System provider. It is an evolution of the Globus Meta Directory System (MDS) gLite actually adopts BDII as Information System. It is based on Lightweight Directory Access Protocol (LDAP) servers. The Relational Grid Monitoring Architecture (R-GMA) Is an implementation of the Grid Monitoring Architecture (GMA) standardized by the Global Grid Forum (GGF) It is a relational implementation of the GMA It is strongly Web Services Oriented To be adopted by next releases of the gLite middleware ????

7. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 6 The LDAP Protocol: Generalities LDAP (Lightweight Directory Access Protocol) It establishes the transport and format of the messages used by a client to access a directory LDAP can be used as access protocol for a large number of databases It provides a standard data model; the DIT (Directory Information Tree) It is the internal protocol used by the EGEE/LCG services to share information

8. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 7 The LDAP Protocol: DIT LDAP structures data as a tree Following a path from the node back to the root of the DIT, a unique name is built (the DN): id=pml,ou=IT,or=CERN,st=Geneva, \ c=Switzerland,o=grid o = grid (root of the DIT) c= US c=Switzerland c=Spain st = Geneva or = CERN ou = IT ou = EP id = pml id=gv id=fd objectClass:person cn: Patricia M. L. phone: 5555666 office: 28-r019

9. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 8 The LDAP Protocol: The Data Model The LDAP information model is based on entries These are attribute collections defined by a unique and global DN (Distinguished Name) Information is organized in a tree-like structure. A special attribute, objectclass, can be defined for each entry. It defines the classes tree corresponding to this entry. This attribute can be used to filter entries containing that object class The information is imported and exported from and to the LDAP server by LDIF files (LDAP Data Interchange Format) dn: objectclass: : dn: objectclass: : Those fields delimited by <> can be defined by the application following a certain schema The schema describes the attributes and the types associated with the data objects

10. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 9 Information Service Systems The gLite Data Model is based on Grid Laboratory Uniform Environment (GLUE) Schema The IS architecture used in gLite is Berkeley DB Information Index (BDII) – has been adopted in LCG middleware as the Information System provider – It is an evolution of the Globus Meta Directory System (MDS) – It is based on Lightweight Directory Access Protocol (LDAP) servers

11. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 10 The Data Model: GLUE Schema

12. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 11 GLUE: Grid Laboratory Uniform Environment Its an information model that describe all those resources that partecipate in the Grid system and that are requested to be discoverable and monitored The same information can be retrieved from different BDIIs relying on different technology (e.g. R-GMA) GLUE: overview

13. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 12 GLUE Schema Describe the Grid resources information stored in the IS Independent from the underlying technology Actual release is mapped on – LDAP – XML – ClassAd (Condor Matchmaking language) The entities of the GLUE Schema are organised hierarchically – Include the concept of Site, Cluster, Computing Element, Storage Element, and an abstraction of service

14. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 13 GLUE Schema Structure Collection of resources owned by a sinle organisation. Contains info on the location, the administrator, web page and so on Site Description of deployed service ServiceStorageElement Set of heterogeneous resources. Contains info on shared directory Cluster 111 * * * Set of homogeneous resources. Contains the size of the set Sub-Cluster ComputingElement Contains details of hardware (features and performance) and software Host 1 * 1 JobVOviewStatePolicyInfo * *

15. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 14 Site Element

16. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 15 GLUE: site GlueSiteUniqueID: TRIGRID-INFN-CATANIA GlueSiteName: TRIGRID-INFN-CATANIA GlueSiteDescription: LCG Site GlueSiteUserSupportContact: mailto: grid-prod@ct.infn.it GlueSiteSysAdminContact: mailto: grid-prod@ct.infn.it GlueSiteSecurityContact: mailto: grid-prod@ct.infn.it GlueSiteLocation: Catania, Italy GlueSiteLatitude: 37.54866 GlueSiteLongitude: 15.036076 GlueSiteWeb: http://www.trigrid.it GlueSiteOtherInfo: TIER 1 GlueSiteOtherInfo: Trigrid Team

17. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 16 GLUE: service GlueServiceUniqueID: infn-rb-01.ct.trigrid.it:7772 GlueServiceName: INFN-CATANIA-rb GlueServiceType: ResourceBroker GlueServiceVersion: 1.2.0 GlueServiceEndpoint: infn-rb-01.ct.trigrid.it:7772 GlueServiceURI: unset GlueServiceAccessPointURL: not_used GlueServiceStatus: OK GlueServiceStatusInfo: No Problems GlueServiceWSDL: unset GlueServiceSemantics: unset GlueServiceStartTime: 1970-01-01T00:00:00Z GlueServiceOwner: trigrid GlueServiceOwner: cometa GlueServiceOwner: inaf GlueServiceOwner: alice GlueServiceAccessControlRule: trigrid GlueServiceAccessControlRule: cometa GlueServiceAccessControlRule: inaf GlueServiceAccessControlRule: alice GlueForeignKey: GlueSiteUniqueID=INFN-CATANIA

18. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 17 Cluster Element

19. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 18 GLUE: cluster and subcluster GlueClusterName: infn-ce-01.ct.trigrid.it GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-short GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-long GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-infinite GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-cert GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-cometa GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-inaf GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-alice GlueClusterService: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-cometa [..] GlueSubClusterPhysicalCPUs: 4 GlueSubClusterLogicalCPUs: 4 GlueSubClusterTmpDir: /tmp GlueSubClusterWNTmpDir: /tmp

20. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 19 GLUE: Host GlueHostApplicationSoftwareRunTimeEnvironment: GLITE-3_0_0 GlueHostApplicationSoftwareRunTimeEnvironment: INFN-CATANIA GlueHostApplicationSoftwareRunTimeEnvironment: MPICH [..] GlueHostArchitectureSMPSize: 4 GlueHostBenchmarkSF00: 1937 GlueHostBenchmarkSI00: 1483 GlueHostMainMemoryRAMSize: 4096 GlueHostMainMemoryVirtualSize: 8192 GlueHostNetworkAdapterInboundIP: TRUE GlueHostNetworkAdapterOutboundIP: TRUE GlueHostOperatingSystemName: Scientific Linux CERN GlueHostOperatingSystemRelease: 3.0.6 GlueHostOperatingSystemVersion: SLC GlueHostProcessorClockSpeed: 2392 GlueHostProcessorModel: Dual Core Opteron 280 GlueHostProcessorVendor: AMD

21. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 20 Computing Element

22. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 21 GLUE: Host GlueCEName: cometa GlueCEUniqueID: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-cometa GlueCEInfoGatekeeperPort: 2119 GlueCEInfoHostName: infn-ce-01.ct.trigrid.it GlueCEInfoLRMSType: lsf GlueCEInfoLRMSVersion: 6.1 GlueCEInfoTotalCPUs: 98 GlueCEInfoJobManager: lcglsf GlueCEInfoContactString: infn-ce-01.ct.trigrid.it:2119/jobmanager-lcglsf-cometa GlueCEInfoApplicationDir: /opt/exp_soft GlueCEInfoDataDir: unset GlueCEInfoDefaultSE: infn-se-01.ct.trigrid.it GlueCEStateEstimatedResponseTime: 61713 GlueCEStateFreeCPUs: 26 GlueCEStateRunningJobs: 70 GlueCEStateStatus: Production GlueCEStateTotalJobs: 70 GlueCEStateWaitingJobs: 0 GlueCEStateWorstResponseTime: 123427 GlueCEStateFreeJobSlots: 26 GlueCEPolicyMaxCPUTime: 2880 GlueCEPolicyMaxRunningJobs: 98 GlueCEPolicyMaxTotalJobs: 0 GlueCEPolicyMaxWallClockTime: 2880 GlueCEPolicyPriority: -10 GlueCEPolicyAssignedJobSlots: 98 GlueCEAccessControlBaseRule: VO:cometa

23. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 22 Storage Element Information about the service (like Name,Port,URL) Storage Area Contains info of available and used disk space,file policies, access rules,etc. Access protocols Contains info about the protocols used to transfer files

24. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 23 GLUE: Storage Element GlueSEUniqueID: infn-se-01.ct.trigrid.it GlueSEName: TRIGRID-INFN-CATANIA:srm_v1 GlueSEPort: 2811 GlueSESizeTotal: 16350 GlueSESizeFree: 16350 GlueSEArchitecture: multidisk GlueInformationServiceURL: ldap://infn-se-01.ct.trigrid.it:2135/mds-vo-name=local,o=grid

25. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 24 GLUE: Storage Area GlueSARoot: cometa:/dpm/ct.trigrid.it/home/cometa GlueSAPath: /dpm/ct.trigrid.it/home/cometa GlueSAType: permanent GlueSALocalID: cometa GlueSAPolicyMaxFileSize: 10000 GlueSAPolicyMinFileSize: 1 GlueSAPolicyMaxData: 100 GlueSAPolicyMaxNumFiles: 10 GlueSAPolicyMaxPinDuration: 10 GlueSAPolicyQuota: 0 GlueSAPolicyFileLifeTime: permanent GlueSAStateAvailableSpace: 16350000000 GlueSAStateUsedSpace: 0 GlueSAAccessControlBaseRule: cometa

26. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 25 GLUE: Access Protocols GlueSEAccessProtocolLocalID: gsiftp GlueSEAccessProtocolType: gsiftp GlueSEAccessProtocolEndpoint: gsiftp://infn-se-01.ct.trigrid.it GlueSEAccessProtocolCapability: file transfer GlueSEAccessProtocolVersion: 1.0.0 GlueSEAccessProtocolPort: 2811 GlueSEAccessProtocolSupportedSecurity: GSI GlueSEAccessProtocolLocalID: rfio GlueSEAccessProtocolType: rfio GlueSEAccessProtocolEndpoint: httpg://infn-se-01.ct.trigrid.it GlueSEAccessProtocolCapability: byte access GlueSEAccessProtocolVersion: 1.0.0 GlueSEAccessProtocolPort: 5001 GlueSEAccessProtocolSupportedSecurity: RFIO

27. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 26 LCG Information System

28. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 27 LCG Information System LCG adopted a combination of solutions (now only BDII). Globus MDS At the lowest level of the information system To discover and monitor resources and publish information Grid Information Security (GSI) credentials Caching BDII At the highest level of the system Because MDS had some troubles in terms of scalability Used by the Resource Broker for the matchmaking process Can be configured by each VO Queries underlying systems periodically (2 minutes) Hierarchical system Information is collected on the leaves of a hierarchical tree and travels towards the root Clients can query the hierarchical tree at every level The higher the level against which queries are made, the older is the obtained information

29. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 28 Collecting Information Gathering of information at different levels Lower level: Grid Resource Information Server (GRIS) Collects information on the state of a given resource One GRIS on top of each resource A set of scripts and sensor that try to extract useful info on the resource Medium level: Grid Index Information Server (GIIS) Collects information on resources of a given site One GIIS for each site Higher level: BDII Collects information on resources of a given VO One BDII for each VO (suggested solution) NOW all levels are based on BDII Way of collecting info Pull model (higher level servers periodically query lower level servers) LDAP query model

30. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 29 Globus MDS (The past) Globus Meta Directory Server (MDS) It is a hierarchical system Based on LDAP servers GRISes are leaves of the tree GIISes are intermediate nodes of the tree The user can query the system at every level The higher the information is in the tree, the older it is Grid Resource Information Service (GRIS) One for each Grid Resource (CE or SE) Collects info on that resource Static or dynamic info Adopts techniques to take measures (such as sensors) Grid Index Information Service (GIIS) One for each site Collects info from above GRISes Caches info according to its validity time Queries above GRISes or GIISes whether needed

31. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 30 BDII overview The Berkley Database Information Index (BDII) Developed within the context of LCG project Solves problems of instability of the MDS occurring when the number of sites grows too much Stays on top of BDII sites One for each VO Centralized system Three levels of hierarchy Accessed by the Workload Management System Way of working One BDII for each resource One BDII for each site collecting info from below BDII systems One BDII for a given VO collecting information from below BDII systems Two LDAP servers, one for write access and one for read access Every two minutes a cron-job runs a script and collects info from a list of BDII sites The list of site BDII is placed in the configuration file of the top BDII

32. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 31 LCG Information System Hierarchy today

33. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 32 BDII top-level BDII site-level BDII resource MDS GRIS provider WMS WN UI FTS Queries Site - Based on ldap - Standardized information provider (GIP) - GLUE-1.3 schema - Top level Used with 230+ sites - Roughly 60 instances in EGEE 2 minutes Berkeley Database Information Index Information & Monitoring Services

34. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 33 BDII overview Every node (except UI and WNs) has a bdii service in order to publish its informations A node in every site collects all site BDIIs and publishes them using a site BDII; The top BDII collects all site BDIIs User can run a set of commands to query the top BDII.

35. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 34 Top BDII vs Site BDII Site BDII It collects all grid BDIIs (for example SE,RB,LFC,etc..) The name of the service is bdii Top BDII It collects all site BDIIs* ; The name of the service is bdii It gives to the RB/WMS all needed informations to match and dispatch user's jobs It can run in the same machine where the RB/WMS is running (it's more fast in answer) *BDII=Berkely Database Infomatin Index

36. Tecnologia dei Servizi Grid e cloud computing - Lezione 8 35 References gLite doc http://glite.web.cern.ch/glite/documentation/default.asp gLite userGuide https://edms.cern.ch/file/722398//gLite-3-UserGuide.pdf https://edms.cern.ch/file/722398//gLite-3-UserGuide.pdf EGEE: The Information System https://twiki.cern.ch/twiki/bin/view/EGEE/InformationSystemOverview https://twiki.cern.ch/twiki/bin/view/EGEE/InformationSystemOverview Berkeley Database Information Index V5 https://twiki.cern.ch/twiki/bin/view/EGEE/BDII https://twiki.cern.ch/twiki/bin/view/EGEE/BDII Glue Usage within EGEE https://twiki.cern.ch/twiki/bin/view/EGEE/GlueUsehttps://twiki.cern.ch/twiki/bin/view/EGEE/GlueUse What is LDAP? http://www.openldap.org/doc/admin22/intro.html#What%20is%20LDAP http://www.openldap.org/doc/admin22/intro.html#What%20is%20LDAP Usage of Glue Schema v1.3 for WLCG Installed Capacity information: https://twiki.cern.ch/twiki/pub/LCG/WLCGCommonComputingReadinessChalleng es/WLCG_GlueSchemaUsage-1.8.pdf https://twiki.cern.ch/twiki/pub/LCG/WLCGCommonComputingReadinessChalleng es/WLCG_GlueSchemaUsage-1.8.pdf