Bridging WSRF services and the EGEE middleware DIS and Keeper

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Bridging WSRF services and the EGEE
middlewareDIS and Keeper

• Pedro Andrade - CERN, Geneva
• (on behalf of the CNR-ISTI team)

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Outline

• DILIGENT Resources
• DIS
• Keeper
• GT4
• gLite
• Features

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DILIGENT Resources

• A DILIGENT resource is anything which information
  can be gathered, stored, monitored and
  disseminated to provide valuable knowledge for
  the creation and management of a DL
• DILIGENT resources are an important piece in
  the design of the DILIGENT services
• Are registered and tracked by the Registration
  Service
• Their profile is disseminated via the Information
  Service

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DILIGENT Resources

• In a typical scenario a DILIGENT resource can be
• DILIGENT Hosting Node (DHN)
• gLiteResource
• DLComponent
• Service
• Running Instance
• Compound Service
• Collection
• DILIGENT resources are different from the usual
  Grid resources or WS-Resources

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DIS

• The DIS maintains
• The most up to date information about the
  available distributed DILIGENT resources that
  belongs to the DILIGENT VO
• The status of the DILIGENT services
• The DIS functionalities are similar to the ones
  provided by UDDI
• In UDDI the registry sets up a service-to-service
  communication
• In DIS, DILIGENT extends this concept and
  provides the communication between DILIGENT
  resources with their consumers

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DIS

• In particular, the DIS
• Allows users and services to discover what
  resources are part of a Virtual Organization (VO)
• Monitors the status of these resources
• Provides query and subscription interfaces for
  any type of resource information
• Provides a trigger interface that can be
  configured to take actions when pre-configured
  conditions are met
• Archives information to allow historical query
  execution

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DIS

• DIS Components
• DIS-IP WSRF service deployed in each DHN
  responsible for gathering the information stored
  in a node. Relies on GT4 MDS Default Index
  service to aggregate the WS-Resources properties
• DIS-IC WSRF service responsible to aggregate the
  information produced by each node. Relies also on
  GT4 MDS Default Index to collect information from
  the DIS-IP or other DIS-IC
• DIS-HLSClient, DIS-Cache, DIS-RGMAClient

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DIS
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Keeper

• The Keeper main role in DILIGENT is the actual
  responsibility for creating the requested DLs
• Such process includes
• Instantiation of the appropriate DILIGENT
  resources
• Configuration of users authorization rights,
  that are required to guarantee access to these
  resources
• Storage of DILIGENT packages
• Deployment of the needed/requested packages
• Dynamic resources re-allocation

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Keeper

• The dynamic resources reallocation is a primary
  feature that allows to fully exploit the Grid
  capabilities in a transparent way
• The Keeper component in charge of managing
  dynamic resource reallocation is the DL
  Management. It coordinates the
• Deployment process of packages within a DL/VO
• Events that occur during the DL/VO life-cycle

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Keeper

• After a new DL is designed, the DL Management has
  to
• Manage the new DL definition criteria
• Manage services dependencies, requirements, and
  QoS parameters
• Interact with the other components to identify
  the appropriate DHN where to deploy the
  identified services
• Interact with the Hosting Node Manager (HNM) of
  the DHNs to start the deployment process
• Report feedback about the deployment activities
• During the DL lifetime, the DL Management has to
• Monitor and update the distributed DILIGENT
  resources making them a unique geographically
  distributed application

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Keeper
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GT4

• The following WSRF and WSN specifications are
  used by the DIS and the Keeper
• WS-ResourceProperties
• WS-ResourceLifetime
• WS-BaseFaults
• WS-ServiceGroup
• WS-BaseNotification
• WS-Topics
• The following WS-MDS services are used by the
  DIS, in particular by the DIS-IC and the DIS-IP
• Aggregator Framework
• Default Index Service
• Trigger Service (planned)
• WebMDS

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GT4

• DIS services are compliant with WSRF and WSN
  standard
• Based on Singleton/Factory pattern
• Stateful WS-Resources
• WS-BaseNotification standard used for
• topic-based notification
• first implementation of a service for brokered
  notification

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GT4

• Some DIS services are based on the WS-MDS
• DIS-IC and the DIS-IP exploits GT4 Default Index
  Service
• Based on Aggregator Source / Sink mechanism
• Use of QueryAggregatorSource
• Use of SubscriptionAggregatorSource
• DIS-Browser portlet (the DIS GUI) uses WebMDS

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gLite

• gLiteResource is a type of DILIGENT resource and
  its profile is published trough the Registration
  Service
• DIS-R-GMA-Client is a plug-in for DIS that
  harvests information from gLite R-GMA server and
  publishes this information as WS-Resource-Properti
  es on the DIS-IC
• The WS-Resources created expose
  WS-ResourceProperties that follows the GLUE
  schema specification
• Another plug-in is being planned for BDII
  (DIS-BDII-Client)

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Features Scalability and Distribution

• The Keeper is responsible for the DIS-IC QoS and
  automatically deploys a new one if necessary.
  Therefore the DIS-IC scales with the number of
  WS-Resources to be managed
• Some of the DIS and the Keeper components are
  distributed in all DILIGENT nodes
• DIS-IP to register each WS-Resource in a DIS-IC
• HNM deploys and hosts new packages in the DHN

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Features Resource Persistence

• The Keeper, in case of DILIGENT resource
  relocation or death, is able to deploy a new
  instance of the resource on a different node,
  persisting its status information
• This mechanism is implemented by the DL
  Management component, that can decide (following
  QoS parameters) if/how to relocate resources in
  order to improve performances

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Thank you !!!

• Questions ??
• http//www.diligentproject.org
• pedro.andrade_at_cern.ch