CLRC and the European DataGrid Middleware

Information and Monitoring Services•The current information service is built on the hierarchical database OpenLDAP (lightweight directory access protocol) as provided by Globus’s Metacomputing Directory Service

•The information published relates to the resources available at a site

•This information is used by the resource broker for resource discovery and job scheduling

computing element

storage elements that are close (not necessarily at the same site)

status supportedprotocols

file statistics

network information between this and other sites

storage element

Example output from the RIPE NCC TTM box

ResourceBroker

StorageElement - A

ComputingElement - A

Information and Monitoring Services

ReplicaCatalogue

Job Submission

UIJDL

Network Monitoring - A

ComputingElement - B

StorageElement - B

Network Monitoring - B

User

Virtual Organisation 1 (Experiment 1)

Middle LayerMSM Interface

Network API

Grid FTP NFS RFIO

Storage Element

Applications

Physical Fabric

Middleware

Information and Monitoring Services

HEP Apps EO Apps Bio Apps

Workload Management

Data Management

Globus Middleware

NetworkingComputing Fabric Mass Storage

CLRC/PPARC participation

•Relational Grid Monitoring Architecture•R-GMA is being developed within the Information and Monitoring Services work package as a new information and monitoring system infrastructure

•R-GMA consists of Consumers, Producers and a directory service (the Registry)

•Producers register with the registry and describe the type and structure of information they want to make available to the Grid

•Consumers query the registry to find out what type of information is available and locate producers that provide such information

•The consumer can contact the producer directly to obtain the relevant data

Red indicates CLRC leadership/management of the work package/group

Mass Storage Management

Network Services

Virtual Organisation 3 (Experiment 3)

Virtual Organisation 2 (Experiment 2)

Network Services•One machine per testbed site is used for network monitoring

•Both active and passive measurements are made

•The information is published via the information service and will be used by the resource broker for job scheduling

•Measurements include: packet loss one-way delay round trip time (RTT) jitter RTT variation

DataGrid Security•Grid certificates enable single sign on to the grid

•Grid certificates issued by certificate authorities

•Each site has a list of trusted authorities

•Developing systems for grid wide authentication and authorisation

Architecture Task Force•The ATF was created to define an architecture for the DataGrid

•It is composed of one person from each of the middleware work packages and invited experts

•The architecture documents define a set of services and their interdependencies

•It has been an important contribution to the success of the first testbed

Storage Element•The Storage Element is an integration project between grid communication protocols and a diversity of mass storage systems

•The Storage Element facilitates centralised brokering of resources via location independent interfaces

•The Storage Element is divided into three layers

Client Applications

Virtual Organisations•A virtual organisation is a dynamic collection of individuals, institutions, and resources with a set of sharing rules that clearly and carefully define what is shared, who is allowed to share, and the conditions under which sharing occurs

•A site may have resources that are allocated to one or more virtual organisation

Middleware•Middleware provides the interface between the applications and the physical fabric

CLRC/PPARC and the DataGrid Project•CLRC staff, and PPARC staff based at RAL, are active in a number of DataGrid work packages

•Particle Physics Applications •Information and Monitoring Services•Mass Storage Management•Testbed Integration•Network Services

Fabric Management

Invocation

Information

Registry Interface

RegistryServlet

Schema Interface

SchemaServlet

Client side

Circular BufferProducerServlet

ConsumerServlet

Consumer

ArchiverServlet

Hidden componentsData BaseProducerServlet

Archiver

Data Base Producer

Circular Buffer ProducerSensor

Application

Application

The Producer Consumer Model

•Architectural Task Force•Security Co-ordination Group•UK DataGrid Co-ordination•Testbed Certificate Authorities group