Grid ComputingA summary of concepts and ideas including

the implementation there-of.

Robert Stallings Thursday, April 20th, 2006

Contents

• Grid Computing– Definition– History– Reasoning– Critical Tasks– Infrastructure– Architecture– Authentication

• Globus Toolkit– Radford and Globus– Globus– Installing Globus– What’s next– Conclusion– Questions and

Answers

History

• Not a new idea

– 1965 Fernando Corbato• “Like a power company or water company”

– 1968 J.C.R Licklider and Robert W. Taylor

Definition

• Server clusters– Clusters of clusters

• Grids join multiple server clusters

Why Gird Computing?

• Quick Facts– Speed doubles every 12 months– Capacity doubles every 9 months– A computer halves in price every 18

months– Performance of WAN doubles every nine

months

• Capacity and WAN Performance is comparable

Critical Tasks

• Involves using remote resources

• Must– Discover they exist– Negotiate access to them– Configure hardware and software– Not lose security.

Critical Tasks

• Critical Tasks– Creating and managing services– Single Sign-on– Transferring large datasets quickly– Form large communities– Maintain existence, state, and usage

policies

Infrastructure

• Internet handles basic communication• Must

– Be broadly developed– Simple– Same functionality as the Internet but more

• Examples:– Science portals– Distributed Computing– Large scale Data analysis– Computer-in-the-loop instrumentation– Collaborative work

Architecture

Authentication

• More difficult

• Computer can be a server AND a client

• Must be able to have one computer be able to use resources on another on behalf of the user.

Authentication

• Requirements– Single Sign-on

– Mapping to local security• Example: Kerberos

– Delegation

– Community Authorization and Policy

Authentication

Overview Conclusion

• Not a new idea

• Several Critical tasks

• New Infrastructure

• New Architecture

• Unique Authentication Procedure

The Globus Toolkit

Experiences with The Modern Grid

Overview

• Radford and Globus

• Globus

• Installing Globus

• What’s next

• Conclusion

• Questions and Answers

Radford and Globus

• NSRL– Network and Security Laboratory

• CREU– Collaborative Research Environment for

Undergraduates

• Current Network– 2 Fedora machines– 1 Windows Machine

Globus

• The Globus Toolkit– The Globus Alliance

• Middleware– GRAM– MDS– GSI– GASS / GridFTP

Setting Up Globus

• Several Basic Steps– Security– GridFTP– Webservices– Reliable File Transfer– WS GRAM

Installation

• Installation– Fedora Core 4

• Easy with RPM

– Windows• Standard EXE

• Linux > Windows– Security– Options– Compatibility

Security

• Create user “Globus”

• Set up full hostname

• Set up dns server

• Create a Simple Certificate Authority– Certificates– Certificate Authority– Single Sign-in

• Add to Mapfile

Security

• 1st machine as Primary Certificate Authority– Secure– Sign certificates– Distribute

• Signing:– Grid-ca-sign –in cert –out signed

GridFTP

• Start Globus Service– Install xinetd.d

• Service Maintainer

– Create GridFTP Service• Gridftp file• Services file

GridFTP

• gridftp file

service gsiftp{ instances = 100 socket_type = stream wait = no user = root env += GLOBUS_LOCATION=/usr/local/globus-4.0.1 env += LD_LIBRARY_PATH=/usr/local/globus-4.0.1/lib 2

server = /usr/local/globus-4.0.1/sbin/globus-gridftp-server server_args = -i log_on_success += DURATION nice = 10 disable = no}

GridFTP

• Services File

• Add to tail end:

# Local services

gsiftp 2811/tcp

Webservices

• Auto-start container– stop-start script

• To start and stop the container easy

– Init.d script• To start the stop-start script on bootup

• Errors– No Reliable File Transfer (RFT).

Reliable File Transfer

• Install Postgres– Database

• Create User Postgres

• Allow Globus User Admin Privilege

Reliable File Transfer

• Create Database– rft_schema.sql

• Edit config file with password and user

• Restart container

WS GRAM

• Use visudo to edit sudoers file– Sudoers

• Who can do what (all one line)globus ALL=(fedoralee1) NOPASSWD: /usr/local/globus-4.0.1/libexec/globus-gridmap-and-execute-g /etc/grid-security/grid-mapfile /usr/local/globus-4.0.1/libexec/globus-job-manager-script.pl *globus ALL=(fedoralee1) NOPASSWD: /usr/local/globus-4.0.1/libexec/globus-gridmap-and-execute-g /etc/grid-security/grid-mapfile /usr/local/globus-4.0.1/libexec/globus-gram-local-proxy-tool *

DONE!(with the first machine)

Second Machine

• Same procedure except..– Trusting 1st machine CA– Certificate Timing– DNS configuration

• Copy second machine for duplication

Common Installation Problems

• No fully Qualified Domain– Create a full Domain Name Service server

• No Mapfile Entry for name

• Invalid Timestamps for certificates

Still to Be Done..

• NTP between computers

• Testing Security

• Porting Globus to First Windows Machines

• Better Troubleshooting Guide

Conclusion

• A lot of time

• Huge learning curve

• Globus is powerful

Questions

?