How do I use the OSG Grid

ILC Detector simulation (SLIC) on the GRID

 This is an example to run SLIC  the Simulator for the Linear Collider on the GRID.SLICis a Geant4-based simulations package that uses an XML geometry input format called LCDD to describe geometry, sensitive detectors and readout geometry.  In this  example SLIC is tared it up and put it on a  web accessible disk space. The grid jobs wgets the tar file unpacks it and runs SLIC
on the stdhep files that is provided with the tar package.
This is only one way to do it, other option include:

• • sending the tar file with the job submission
  • install SLIC on nodes that are visible to the grid worker nodes

Prerequisites for sending jobs to the GRID are:
1) get a DOE grid certificate: http://security.fnal.gov/pki/Get-Personal-DOEGrids-Cert.html
This page also explains how to export the certificate from the browser and how to deal with directory permissions and such.

2) register to the ILC VO (Virtual organization) http://cd-amr.fnal.gov/ilc/ilcsim/ilcvo-registration.shtml
that will guide you to: https://voms.fnal.gov:8443/vomrs/ilc/vomrs

3) Everything is set up  on ILCSIM. So to try things out it is recommeneded to  get an account on ILCSIM using the following form http://cd-amr.fnal.gov/ilc/ilcsim/ilcsim.shtml

If you don't use ILCSIMas the gateway he Virtual Data Toolkit (VDT) needs to be installed on the machine from where you want to submit jobs.  And as always if you plan on running any grid services you'll need a host certificate for your machine.

The Example

The SLIC test job below actually tries to store the output in mass storage using the grid srmcp file transfer tool. But It's probably easirer to transfer the output via condor I will provide an example once I tested it.

.  /fnal/ups/grid/vdt/setup.sh
voms-proxy-init -voms ilc:/ilc/detector
(give passwd etc.)

to submit the job do:
condor_submit mytestslicjob.run

where the job description file mytestslicjob.run looks like: 

universe = grid
type = gt2
globusscheduler = fngp-osg.fnal.gov/jobmanager-condor
executable = /home2/ilc/wenzel/grid/test_slic.sh
transfer_output = true
transfer_error = true
transfer_executable = true
log = myjob.log.$(Cluster).$(Process)
notification = NEVER
output = myjob.out.$(Cluster).$(Process)
error = myjob.err.$(Cluster).$(Process)
stream_output = false
stream_error = false
globusrsl = (jobtype=single)(maxwalltime=999)
queue

which triggers the following script:

#!/bin/sh -f
wget http://kyoto.fnal.gov/wenzel/SimDist.tgz
tar xzf SimDist.tgz
cd SimDist
printenv
scripts/slic.sh -r 5  -g sidaug05.lcdd -i ffHAA_2k.stdhep  -o ffHAA_2k
ls ffHAA_2k.slcio
#This sets up the environment for osg
. $OSG_GRID/setup.sh
source $VDT_LOCATION/setup.csh

To run some commands directly on the grid head nodes use a syntax like this:

globus-job-run fngp-osg.fnal.gov/jobmanager-condor /bin/ls /grid/home/cmssoft
globus-job-run fngp-osg.fnal.gov/jobmanager-condor /usr/bin/printenv