1. GridFE: Web-accessible Grid System Front End Jared Yanovich, PSC Robert Budden, PSC

2. GridFE2 Preface User adoption of grids remains limited by obstacles in usability –Ease of access and use of a grid are essential –Bad initial user experiences are hard to overcome Web-based front ends can ease user access to a grid, including facilities to: –Simplify user authentication and credential management –Guide users in gathering job submission parameters and submitting jobs –Monitor jobs submitted and gather output

3. GridFE3 SuperComputing Science Consortium –Regional partnership National Energy Technology Laboratory Pittsburgh Supercomputing Center West Virginia University Carnegie Mellon University University of Pittsburgh WV Governor's Office of Technology Institute for Scientific Research Duquesne University Waynesburg College NASA IV & V :NASA IV & V –Objective: enhance access to computational resources to advance scientific research –http://www.sc-2.psc.edu/

4. GridFE4 (SC) 2 SABER Grid Common grid infrastructure between computational resources at DOE NETL, PSC, and WVU –Commodity Intel IA32 clusters / Linux Accessible by researchers, faculty and students at (SC) 2 member sites Used for research computing and computer science coursework

5. GridFE5 Designed to be easy to use Developed for use with Globus –Globus is very common –Many APIs for accessing –Globus protocols exist and are readily available Features supported by GridFE: logging in/authentication, job submission, job output retrieval

6. GridFE6 Logging In HTTP authentication over SSL is used to log in Messy details of certificates all handled on behalf of user

7. GridFE7 Logging In (2) For SABER, accounts are managed through Kerberos To authenticate on the command line, the user must run: –kinit –kx509 –kxlist GridFE handles this on behalf of the user

8. GridFE8 Logging In With mod_fum HTTP authentication handled by mod_fum, an Apache module written to leverage KX509 to generate grid proxy certificates Apache Web Browser Client mod_fum Kerberos Domain Controller

9. GridFE9 mod_fum (2) After successful Kerberos authentication via libkrb5, mod_fum generates a KX509 certificate from the Kerberos ticket using libkx509 from the KCA/KX509 project A short-lived X.509 certificate is generated by the KCA corresponding to the KX509 certificate via libkx509 The X.509 certificate is later used to authenticate to the grid

10. GridFE10 Portal Interface Hyperlinks to common grid functionality: Submit jobs Previously submitted jobs’ status SABER news Proxy certificate information Grid node availability

11. GridFE11 Job Submission HTML form controls for all job submission parameters Job identification Executable path Target host Files involved Equivalent to command line invocation of globus-job-submit

12. GridFE12 Job RSL Resource specification language (RSL) describes job Used by job submission manager and is needed to submit jobs It also allows: –Job quantization – specify all resources associated with the job –Useful for re-running same job GridFE constructs RSL for jobs on behalf of the user, additionally providing optional access to it

13. GridFE13 Job Status Job status page lists previously submitted jobs and their status Comparable to executing globus-job-status for each job submitted Follow a job to retrieve output

14. GridFE14 Job Output Job output page shows any output the job generated Easy to download and save Equivalent to invoking the globus-job- get-output command line utility

15. GridFE15 GridFE Backend Architecture Apache Tomcat (Java Servlet Runner) Java Interpreter GridFE Servlet Modules CoG Libraries Web Client 1 2 3 4 5 6 7 8 Phew!

16. GridFE16 System Design Authentication handled by custom Apache module mod_fum Grid functionality divided into Web pages Web pages generated by Java servlet Grid Commodity Toolkit (CoG) used by GridFE Java servlet to participate in grid protocols CoG

17. GridFE17 GridFE Java Servlet Class Hierarchy GridFE Page OOF – Generic object output formatting JASP – Java Web application service routine package gridfe – grid- and Web page-related Page Header Paragraph Forms Table Submit job Retrieve job output Node availability Miscellaenous Routines for Web applications GridJob Certificate RSLelement

18. GridFE18 Related Work Other portals provide Web-based access to grid systems: OGCE, and GPDK However, they are not tailored for a Kerberos authentication environment Also, GridFE consists of a simpler interface providing only essential grid functionality, lowering the learning curve to grid adoption

19. GridFE19 Conclusion Grid systems are an important computational resource It is essential that grid systems be accessible and easy to use GridFE was designed to reduce obstacles to allow users to harness the power of grid systems –Easy-to-use interface –Authentication and credential management simplified –Tools to assemble job descriptions, submit and monitor jobs, and gather output –Instructional components to help users learn about and use grid middleware

20. GridFE20 Future New features planned: –Enhanced job submission controls –Replica Location Service support Long-term support planned: –Grid information/service browsing –Enhanced data transfer support –Grid workflow management

21. GridFE21 Further Information “GridFE: A Web-accessible Front End to a Grid System”, R. Budden et al., PSC, Oct 2005, http://www.psc.edu/~yanovich/gridfe.pdf http://www.psc.edu/~yanovich/gridfe.pdf KCA/KX.509 Project, http://www.citi.umich.edu/projects/kerb_pki/ http://www.citi.umich.edu/projects/kerb_pki/ Apache Web Server Project, http://www.apache.org/ http://www.apache.org/ Globus Alliance, http://www.globus.org/http://www.globus.org/ Grid Commodity Toolkit, http://www.cogkit.com/http://www.cogkit.com/