http://www.grid-support.ac.uk http://www.ngs.ac.uk The Storage Resource Broker and the NGS Slides from Peter Berrisford, RAL For a full SRB tutorial, see: http://www.niees.ac.uk/events/srb http://www.nesc.ac.uk/ http://www.pparc.ac.uk/ http://www.eu-egee.org/ • http://www.sdsc.edu/srb/ 2 What is SRB? • Storage Resource Broker (SRB) is a software product developed by the San Diego Supercomputing Centre (SDSC). • Allows users to access files and database objects across a distributed environment. • Actual physical location and way the data is stored is abstracted from the user • Allows the user to add user defined metadata describing the scientific content of the information Peter Berrisford 3 RAL How SRB Works • MCAT Database c d MCAT Server b e f SRB A Server SRB B Server 4 major components: – The Metadata Catalogue (MCAT) – The MCAT-Enabled SRB Server – The SRB Storage Server – The SRB Client g a SRB Client Peter Berrisford 4 RAL The MCAT Database • The MCAT database is a metadata repository that provides a mechanism for storing information used by the SRB system. • Includes both – Internal system data required for running the system – Application (user) metadata regarding data sets being brokered by SRB. Peter Berrisford 5 RAL The MCAT Server • At least one SRB Server must be installed on the node that can access the MCAT database. This is known as the MCAT-Enabled SRB Server. • MCAT SRB Server works directly against the MCAT database to provide SRB Services • All other SRB Servers interact through the MCAT Server Peter Berrisford 6 RAL The SRB Server • The SRB Server is a middleware application that accepts requests from clients and obtains/queries/manages the necessary data sets. • It queries the MCAT SRB Server to gather information on datasets and supplies this back to the SRB client. Peter Berrisford 7 RAL SRB Client Tools • Provide a user interface to send requests to the SRB server. • 4 main interfaces: – – – – Command line (S-Commands) MS Windows (InQ) Web based (MySRB). Java (JARGON) • Web Services (MATRIX) Peter Berrisford 8 RAL Concepts • Location: A physical node running an SRB Server • Physical Resource: A storage area managed by an SRB Server • Logical Resource: One or more Physical Resources – can be distributed • Collection – Data abstraction of resources Peter Berrisford 9 RAL Deployment Structure Disk Farm Database Servers @ Manchester MCAT DB1 SRB Server DB n MCAT Server @ Manchester Online Replication Failover link User MCAT Server @ RAL MCAT DB1 SRB Server DB n Database Servers @ RAL SRB server @ Leeds Resource Driver Disk Farm SRB server @ RAL Resource Driver Disk Farm SRB server @ Oxford Resource Driver Disk Farm SRB server @ HPCX Resource Driver Disk Farm Peter Berrisford 10 RAL SRB practical 11