Grid tutorial

Grid tutorial at CERN

Get your grid certificate

• To get your grid certificate follow instructions in: http://lcg.web.cern.ch/LCG/users/registration/registration.html Be careful when choosing your grid password, you will need to remember it afterwards

• Export Your Certificate into Your AFS directory (These instructions are copy-paste from: http://www-pnp.physics.ox.ac.uk/~powell/documents/GridCert.html) In order to use your certificate with any of the LCG applications you must export both your certificate and private key from your Mozilla browser and convert them to the neceassry format. To do this:
  • Open your Mozilla browser and click on Edit and then on Preferences.
  • Expand the Privacy & Security tab and select Certificates.
  • Click on the "Manage Certificates..." button.
  • Select your User Certificate (named eScience) and click the Backup button.
  • Mozilla will prompt you to choose a filename and location for the exported file containing both your certificate and private key. Save this locally on your ppslgen space with the file extension ".p12" (in my example i called it teregrid.p12). You will have to enter a new password to export the file and encrypt it (PASS PHRASE).

• Convert the user key using (Instructions from: https://edms.cern.ch/file/454439//LCG-2-UserGuide.html#SECTION00061300000000000000):

openssl pkcs12 -nocerts -in teregrid.p12 -out userkey.pem
openssl pkcs12 -clcerts -nokeys -in teregrid.p12 -out usercert.pem
chmod 400 userkey.pem
chmod 444 usercert.pem

• Login into lxplus:

cd ~
mkdir .globus

Copy in the .globus directory the two files you have in your local machine: userkey.pem and usercert.pem

source /afs/cern.ch/project/gd/LCG-share/current/etc/profile.d/grid_env.csh

Note: Because of problems with versions of SL3/SL4 you may have to substitute "previous" for "current". (or vice versa!) (Instructions from: https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBookStartingGrid)

voms-proxy-init

You'll be prompted for your password. You are set up

Useful links

• http://lcg.web.cern.ch/LCG/users/registration/registration.html
• http://www-pnp.physics.ox.ac.uk/~powell/documents/GridCert.html
• https://edms.cern.ch/file/454439//LCG-2-UserGuide.html#SECTION00061300000000000000
• https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBookStartingGrid

Useful links

• https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBookStartingGrid
• The "Using the grid" section in Atlas work book https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBook

-- TeresaFonsecaMartin - 02 Oct 2007