Using ganga 5 with athena version 14 at Liverpool

Step 1: Get a grid certificate

This is documented elsewhere

Step 2: Log in and set up

The node hepgrid1 is our permanent grid User Interface (UI). However, any of the hepshell nodes (alpha ... epsilon) can also be used as temporary UIs, perfectly suitable for non-intensive tasks such as dq2-ls and job submission using ganga. Set up your favourite athena release on any of these nodes, for example as described here (Note: you will not be able to klog into CERN on hepgrid1). Once this is done, source the grid setup script:

source /batchsoft/atlas/grid/setup.sh

You will be asked for your grid pass phrase during the execution of this script. It's important not to do these steps the other way around, as the grid tools (especially ganga) need to detect the athena environment in order to function correctly.

Step 3: First-time use of ganga

If you have not used ganga before (or not recently), you will need to create the configuration file ~/.gangarc. To do this, simply execute this command:

ganga -g

Many changes need to be made to the default configuration to run ganga at Liverpool - almost all of these are dealt with in the grid setup script from Step 2. However, you do need to specify where you want your job information stored. By default, this would be in ~/gangadir/ which is not ideal as this directory can get rather large depending on what you're doing. Search your .gangarc file for "gangadir", and insert the location you want. For example:

gangadir = /scratch/flowerdew/gangadir

Step 4: Run a job

You now (hopefully) have everything set up OK, time to submit a job:

ganga
> execfile('../share/MyFavouriteJobSubmissionScript.py')

For more information on using ganga and submitting jobs, see the relevant section of the physics WorkBook.

-- MikeFlowerdew - 01 Jul 2008