UC Davis Tier 3 Twiki

The UC Davis Tier3 consists of 4 WAN connected front end machines. These are cms.tier3 (CE, gridftp), agent.tier3 (GUMS, squid), se.tier3 (bestman, hadoop, phedex) and shell.tier3 (ssh, nfs, local condor ). We currently possess 40 1U worker nodes each with 2 quad core AMD Opteron processors and 12GB of RAM. Each core has one job slot in condor shared amongst condor_g and condor. Below are administrative documents and user guides.

To access UCD_T3

CRAB's nature is to submit and run the job on free resources by default. In order to save data to the tier3 or to force the job to run on the tier3 (provided your dataset is available on the T3) do the following:

To run on the tier3:

[GRID]
ce_white_list = T3_US_UCD

To save to the tier3:

[USER]
.
.
storage_element = T3_US_UCD

The second method of using the tier3 is with a local account using local condor. To do this send an email to help@cseNOSPAMPLEASE.ucdavis.edu with the following information:

Your Name:
Desired User Name:
Supervisor's Name:
Your ssh public key. 

Follow the first 3 steps of this article if you don't know how to generate an ssh public private key combination. After approval you will be able to login interactive to shell.tier3.ucdavis.edu. While logged in to this machine you will be able to ssh to each worker node separately (this is not recommended) or submit jobs to the worker nodes via condor. Please do not run intense jobs on shell.tier3 directly.

Utilization of the Tier 3

To use the tier 3 with CRAB please see the above. To use the tier 3 locally you may:

ssh to Each Node Individually Simply ssh to each node following the following name convention: ssh cX-X. For example ssh c0-0. See the ganglia page for node names.

Use Local Condor To Submit to the Local Queue If you already have a condor submission script that you wrote use that. If not the following scripts are provided by me to help you get going, you need a working CMSSW cmsRun configuration fragment to do this. First copy the scripts condor_cmssw.jdl and cmssw_condor.sh to the directory with your config file from /share/apps/cmssw_scripts. Next edit the condor_cmssw.jdl with appropriate values in the bracketed fields. Then submit condor_cmssw.jdl to condor. That's all you need to do!