Data Grid: Storage
Resource Broker
Mike Smorul
<toaster@umiacs.umd.edu>
SRB Overview

Developed at San Diego Supercomputing
Center.

Provides the abstraction mechanisms
needed to implement data grids, digital
libraries, and persistent archives for data
sharing, data publication, and data
preservation.
SRB Concepts: Architecture
SRB Concepts: Components
MCAT SRB Server
MCAT RDBMS
Oracle Client
SRB Server
User
SRB Server
SRB Server
SRB Server
Storage Driver
Storage Driver
Storage Driver
Storage Space
Storage Space
Storage Space
SRB Vault
SRB Vault
SRB Vault
SRB Concepts: Access control

Granular access permissions including:
 Multiple
primary owners of grid objects
 Restrictions on collection and metadata browsing
 Resource restrictions
 Standard unix-like permissions

Distributed access through domains within sites
and across SRB zones
SRB Concepts: Federation

A Federation enables SRB zones to recognize and interact with other zones it opens
many possibilities in the types of interaction

Federation Enables Fragmentation of MCAT Database
An MCAT fragment coming down due to network or system failure does not bring the entire SRB
down. The other sections continue to provide the server leaving only one section temporarily
inaccessible.

With federation, meta data can be made to reside closer to the resource by hosting a
MCAT server closer to the resource.
This enables reducing network latency, thus may enable an overall improvement in performance
when an SRB network spans across large geographical distance.

Federation enables local administrative control of resources enabling the notion of
Virtual Organizations (VO) and also make it easy for a new VO to join the network

It also enables easy replication and transfer of documents between VO
Implemented
Standards/Protocols

GSI based authentication
 Globus
tickets can be used to authenticate against
the SRB

MATRIX project provides a WSDL interface into
the SRB

Able to interface and abstract standard storage
devices
Interfaces to the SRB

Scommands

Unix file system like interface
 Versions available for Unix,
Dos and Mac

inQ –

Windows Explorer style
interface
 Version available for Windows

My SRB


Web Browser interface
Client access API



C API
JARGON – Java API to SRB.
MATRIX – SRB Workflow
management system
Metadata
System level (checksums, guid, structural)
 Application level per object or collection

 User-defined
attributes (attribute/value pairs)
 Extensible schema on mcat
 Database Access Interface (SQL
passthrough)

Bulk operations on Metadata, upload
Maturity

SDSC controlled SRB installations:
 >4,900
users
 17 Installations

NARA, Teragrid, BIRN…
 50.2
million files
 305Tb total storage
Support

Community and developer support
 Srb-chat
mail list
 Bugzilla for bug/feature tracking
 Limited developer access
 Periodic workshops
Open/Proprietary

Mostly open-source license
 Free
to academic and government research
groups.
 http://www.sdsc.edu/srb/srbOpenSource.html

Commercial services need to contact
UCSD Technology transfer office.
Setup Cost

Simple setup of MCAT and first srb master





Autoinstall script to configure database, srb, and storage
resource
UMD setup in under two hours.
GUI based administration utility
Multiple interfaces to allow for simple client access
Large SRB installations
may require database expertise
for maintaining MCAT database
Future Plans
OGSA compliant interface
 Expanded Federation capabilities
depending on community needs
 See Bugzilla for more

 http://srb.npaci.edu/bugzilla/
More Information

SRB website
 http://www.sdsc.edu/srb/