PRAGMA Users Guide


 

What the PRAGMA Grid is For?

The PRAGMA Grid is established May 18, 2004 by PRAGMA Resources Working Group. This grid is composed of cluster systems and technical expertise from PRAGMA members and friends institutions. It provides the infrastructure and a collaborative environment for grid middleware and grid applications to interoperate and improve. It's also where PRAGMA researchers can innovate and experiment with new approaches and new solutions to make the grid easy to use. Please see more detail information on PRAGMA Grid resources.

Who should join PRAGMA grid?

Any institutions have been working in grid applications and middleware and are interested in building a long term collaborative relationship with PRAGMA communities are welcome to join PRAGMA grid.

Any individual researchers interested in working with PRAGMA grid can work thru their home institutions or thru existing PRAGMA grid member institutions which they already have working relationship with.

PRAGMA grid does not require every member institution to contribute hardware resources, but for all practical purposes, it’s a lot easier for application drivers to access PRAGMA grid from a local node that’s a part of PRAGMA grid.

What kinds of applications are suitable to run in PRAGMA Grid?

1.     Real science and real grid applications - per PRAGMA charter.

2.     Applications can submit jobs through globus gatekeeper to local job schedulers (SGE, PBS, LSF, SQMS, etc.).
This enables resource sharing in PRAGMA grid.

3.     No absolute rules, and things may change as better technologies develop. In case of any questions on the suitability of your application, contact Cindy Zheng.

How to go about in getting an application run in PRAGMA Grid?

1        Request to run application in PRAGMA grid

Email Cindy Zheng, to introduce

·        yourself

·        your affiliation with PRAGMA

·        description of your application (what scientific problem it's trying to solve)

·        the application/middleware you'd like to run

·        the person who will be driving the application run

·        your goal (results and schedule)

·        resources required for your application.
If you want to know what resources we have now in PRAGMA Grid, you can browse our resources info and check our resources availabilities in real-time.

If your application is suited to run in PRAGMA grid, Cindy will add you into the appropriate PRAGMA mailing lists and setup an account for you at wiki.pragma-grid.net.

2        Document your application

After you receive wiki account info, please follow the application document guideline and template  to document your application at http://goc.pragma-grid.net/wiki/index.php/Applications and inform Cindy Zheng when done.

3        Request for PRAGMA Grid access

Currently, PRAGMA grid is in transition to VOMS based authentication mechanism - some sites are using VOMS and some sites are not yet. You can choose to use either one or both of the two sets of resources:

a)     To access VOMS-aware sites, follow the steps in PRAGMA VOMS User Guide

b)     To access non-VOMS-aware site, follow the steps in PRAGMA User Account Application

4        Setup and Test ssh and globus access

We will setup and test with a SDSC cluster first, to create and verify user info tarball before asking all sites to do the setup.

a)     Cindy will create a tarball with the info you provided in step 2, setup your account on a SDSC cluster and inform you the <hostname> and <username>.

b)     You test access

i)       Test ssh access

On your local UNIX system where ssh client client software is installed, make sure that your ssh private key is correctly installed in ~/.ssh directory. List of ~/.ssh directory should show both public and private key files. For example:

$ ls -l ~/.ssh

-rw-------  1 cindy cindy  951 Mar  7  2007 id_rsa

-rw-r--r--  1 cindy cindy  234 Mar  7  2007 id_rsa.pub

(Make sure that you have a backup copy of these files.)

Then run

$ ssh <username>@<hostname>.sdsc.edu

You should be prompted for a passphrase. Enter the passphrase you used to create the ssh key before and this should enable you to login. On SDSC Rocks clusters, as a new user on your first login, you will be asked to create a ssh key. This ssh key should only be used internally within the cluster. For simplicity, hit the return key 3 times to accept the default location for .ssh key files and to create the passphrase with empty strings.

If you failed ssh login, then run

$ ssh –v <username>@<hostname>.sdsc.edu

And email the output to Cindy.

ii)     Test Globus access

On your local UNIX system where Globus software is installed, make sure that your Globus user certificate and key files are correctly installed in ~/.globus directory. List of ~/.globus directory should show the certificate and key files. For example:

$ ls -l ~/.globus

-r--------  1 cindy cindy 4998 Jan 25  2007 usercert.pem

-r--------  1 cindy cindy 1743 Jan 25  2007 userkey.pem

(Make sure that you have a backup copy of these files.)

Then run

$ grid-proxy-init

It will prompt you for your “GRID pass phrase”. Enter the passphrase you used when you requested your Globus user certificate. If successful, it will return “Creating proxy ... Done”. Then, run

$ globusrun -a –r <hostname>.sdsc.edu

If successful, it will return “GRAM Authentication test successful”.

If any problems, please email all the output from the above commands to Cindy.

iii)   Test job submission

If the Globus access tests are successful, you can test job submission by running

$ globus-job-run <hostname>.sdsc.edu/jobmanager-sge /bin/hostname

Depending how busy the <hostname>.sdsc.edu is (you can check by ssh login to the host and run “qstat –f”), you may need to wait until the job get its turn to execute. Then it should return a host name or a node name. (On SDSC Rocks systems, you may ignore warning messages in this output, as long as it returns a host name or a node name, the job submission is successful.)

If the job submission failed, please email the output to Cindy.

5        Setup and test at more sites

When all the tests in step 5 confirmed to be successful, Cindy will upload your user info tarball to the PRAGMA Grid Operation Center (GOC) web side and email all PRAGMA grid site admins, refer them to your wiki documents for your application requirements and ask the qualified sites to setup your account.

As each site inform you that your account has been setup, repeat step 5 to test your ssh and globus access at each site. Note that each site may use different job schedulers (PBS, SGE, …). See http://goc.pragma-grid.net/pragma-doc/computegrid.html and http://goc.pragma-grid.net/wiki/index.php/Site_status_and_tasks for system, software and contact info for each site.

You can also create and run script to find out which cluster is ready or having problems.

If you have any problems with any site, please email detail info to the site contact and cc Cindy.

6        Run and document

Don’t wait for all sites setup your access. You can start testing your code on 1 or 2 clusters first. If successful, expand to more sites.

Through-out the application run, please continue to document your application status, logs, data, results at the PRAGMA wiki site.

We hope to hear your success and lessons learned, and to see our long-term collaborative relationship grow.