login to any of the interactive machine(unt3int01-05), run the following commands

#localSetupATLAS  

or run

export ATLAS_LOCAL_ROOT_BASE=/cvmfs/atlas.cern.ch/repo/ATLASLocalRootBase

source /cvmfs/atlas.cern.ch/repo/ATLASLocalRootBase/user/atlasLocalSetup.sh

List the available versions of root

# lsetup -h root 

Select one of the above listed versions,

#lsetup "root 6.32.06-x86_64-el9-gcc13-opt"

-- WenjingWu - 21 May 2019