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You can run fireworks (cmsShow) on your laptop or desktop machine and access data directly from our Tier-2 dCachestorage element.
Just put the prefix 'root://dcache-00xrootd.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/' in front of the LFN.

Example:

Code Block
xml
xml

> cmsShow root://dcache-00xrootd.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/store/data/BeamCommissioning09/MinimumBias/RAW-RECO/SD_AllMinBias-Jan23Skim-v1/0014/AC5CE429-B809-DF11-85F1-0026189438A9.root

To copy a single file from the Tier-2 dCache storage element to your local machine (laptop or desktop) you can use the command xrdcp.
First you need to initialize your ROOT or CMSSW environment (run cmsenv).

Example:

Code Block
xml
xml

> xrdcp root://xrootd.rcac.purdue.edu//store/group/ewk/DY/DYM20/ntuple_skim_96_2_z5w.root my.root

...

If you are using ROOT, you can open files from our Tier-2 dCache storage element just like you would any other file:

Code Block
xml
xml

TFile::Open("root://dcache-00xrootd.rcac.purdue.edu/pnfs/rcac.purdue.edu/data/store/data/BeamCommissioning09/MinimumBias/RAW-RECO/SD_AllMinBias-Jan23Skim-v1/0014/AC5CE429-B809-DF11-85F1-0026189438A9.root");

...

Check for file availability with:

Code Block
xml
xml

> xrd cms-xrd-global.cern.ch existfile /store/myfile.root 

Direct access: ROOT and CMSSW PoolSource can open a remote file directly through AAA

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xml
xml

> “root://cms-xrd-global.cern.ch//store/myfile.root” 

Make a local copy:

Code Block
xml
xml

> xrdcp root://cms-xrd-global.cern.ch//store/myfile.root /localpath/myfile.root 

...