CMSSW installation

CMSSW

Automatic installation

Installing and upgrading CMSSW can be made automatic, by providing the CMSSW team at CERN a special CMSSW installation account and enough diskspace (~ 200 GB?). (more to be written later).

Manual installation using apt-rpm

CMSSW with most of it's dependencies are available as precompiled RPM packages in an APT repository, makeing the installation relatively simple. Complete installations are available here: https://twiki.cern.ch/twiki/bin/view/CMS/CMSSW_aptinstaller, quick instructions below:

export SCRAM_ARCH=slc4_ia32_gcc345
export VO_CMS_SW_DIR=/home/opt/cms/cmssw  # Or whatever directory you want to use
mkdir $VO_CMS_SW_DIR
cd $VO_CMS_SW_DIR
wget http://cmsrep.cern.ch/cmssw/bootstrap-$SCRAM_ARCH.sh
sh -x bootstrap-$SCRAM_ARCH.sh setup -path $VO_CMS_SW_DIR
source $SCRAM_ARCH/external/apt/0.5.15lorg3.2-CMS3/etc/profile.d/init.sh
apt-get update

apt-get install cms+cms-env+1.0      # These two lines are necessary because of a
apt-get install cms+cms-common+1.0   # bug. Might become unnecessary in the future.

apt-get install cms+cmssw+<VERSION_TAG>

A few things to note

• Use SCRAM_ARCH=slc4_ia32_gcc345 (rather than slc4_amd64_gcc345) even on 64 bit (x86-64) hardware
• $VO_CMS_SW_DIR has to be the same on the installation node as it will be on the computation nodes.
• New versions are usually released as separate packages, rather than new versions of the same package. "apt-get update && apt-get dist-upgrade" will therefore typically not upgrade CMSSW to the latest version.
• To later add/upgrade to new versions, you can omit some of the above steps and do

  export SCRAM_ARCH=slc4_ia32_gcc345
  export VO_CMS_SW_DIR=/home/opt/cms/cmssw  # Or whatever directory you want to use
  cd $VO_CMS_SW_DIR
  source $SCRAM_ARCH/external/apt/0.5.15lorg3.2-CMS3/etc/profile.d/init.sh
  apt-get update
  apt-get install cms+cmssw+<VERSION_TAG>
  

SITECONF

blah, blah, blah.