Using the Grid/Job startGridSession

Starting a gridsession

The easiest way to start a session on the LifeScience Grid is to use the script "startGridSession <VO Name>".

This script will:

1. generate a proxy certificate,
2. store it in the Myproxy server
3. delegate it to the WMS with your user name as the delegation ID (DID).

Your jobs will now be able to run for week. The WMS, responsible for the scheduling of your job, will renew the proxy certificate of running jobs every 12 hours automatically.

NOTE: If you do not use the LifeScience Grid and you do not have the startGridSession script installed on your local UI, you may download it here. First download the script and save it in your home directory and make it an executable with the command "chmod 744 StartGridSession.sh". You can now run it from every directory with "~/StartGridSession.sh <VO Name>". Consistency: watch out with the CaSE of this script, the mediawiki stores it with a Capitalized first letter. Use rename.

Normally, jobs that were submitted but did not finish within the lifetime of your proxy certificate will be aborted. However — the WMS is able to automatically renew the proxy certificate —, the twelve hours is expanded to a full week.

Operations run by this script

1. voms-proxy-init -voms lsgrid: This creates a proxy certificate that enables you to access the Grid for 12 hours.
2. myproxy-init -d -n: This stores a week long proxy certificate in the Myproxy server.
3. glite-wms-job-delegate-proxy -d $USER: This delegates your credentials to the WMS. The -d $USER flag acts as pointer which you can use in your job submissions to avoid repeating delegation.

And now you are ready to submit jobs to the Grid!

• To start your Grid session:

startGridSession <VO Name>, example: "startGridSession lsgrid"

• To see how much time there is left on your Grid session:

 myproxy-info -d

• To renew your Grid session:

startGridSession <VO Name>

• Example of the command to submit a job, note the use of -d $USER to tell your job that it should use your delegated proxy certificate (more on that in the rest of the tutorial):

glite-wms-job-submit -d $USER -o myjobs job.jdl

• To end your session:

myproxy-destroy -d

NOTE: myproxy-destroy will not terminate any job. Jobs will continue to run and will fail when the the proxy certificate that was used at the time of submission, expires. Use glite-wms-job-cancel <JobID> to cancel running jobs.