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Request a grid certificate and membership in the ATLAS VO: https://atlassoftwaredocs.web.cern.ch/ASWTutorial/basicSetup/grid_vo/
Export the certificate from your browser (or keychain) and save as .p12 file. Copy the file over to the cluster.
Install the certificate.
setupATLAS
lsetup rucio
Check that it works using:
setupATLAS
lsetup rucio
voms-proxy-init -voms atlas
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