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/
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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
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