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Software available from the T2 UI machines

The T2 has many more software than what is available directly from the M machines. All are provided by cern's centrally managed files system called cvmfs. They are divided in a CMS specific area and a more general area aimed at high energy in general.
The CMS specific area comes with a home brew script that makes it easy for searching specific versions of the software you need. However, the set-up is a lot more complicated than the general purpose area. Therefore we recommend the general purpose area unless you do not find the specific version you need in it.

General purpose area

Instead of trying to explain in details how the /cvmfs sub-directories are organized, we will limit ourselves in this wiki to give some relevant links about the general purpose area:

Highlevel description of the software packages and how they are grouped in LCG Configurations
Website of the SFT group managing what's in /cvmfs/sft.cern.ch

Load a specific software repository

The software packages are grouped in LCG Configurations. In each of these configurations, you will normally find set of software versions that are compatible with each others. To get the list of LCG Configurations :


Now, let's say you want to know more about the "LCG_93c" configuration :

/cvmfs/sft.cern.ch/lcg/views/checkSetupViews.sh LCG_93c
Available <arch-os-compiler> for LCG_93c : 

If you are on an SL6 UI and we want gcc62, we have to issue the following command :

source /cvmfs/sft.cern.ch/lcg/views/setupViews.sh LCG_93c x86_64-slc6-gcc62-opt

Check the version of gcc :

$ gcc -v
Using built-in specs.
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-6.2.0/configure --prefix=/build/pmendez-sftnight/install-620local -with-system-zlib --disable-multilib --enable-languages=all
Thread model: posix
gcc version 6.2.0 (GCC) 

At this moment your environment has been changed to use all the versions in this specific software area.

Be careful when loading a different version of python

When the software reopistory you want to use contains a version of python that is higher than the one installed on the cluster, you might encounter a problem with the gfal libraries:

'import site' failed; use -v for traceback
Traceback (most recent call last):
  File "/usr/bin/gfal-mkdir", line 24, in <module>
    from gfal2_util.shell import Gfal2Shell
ImportError: No module named gfal2_util.shell

This happens because of a mismatch between the software used and the libraries installed. The easiest solution is to use python 3 and a specific version of the UI (user interface) software like in the following example:

    source /cvmfs/sft.cern.ch/lcg/views/setupViews.sh LCG_93python3 x86_64-slc6-gcc7-opt
    source /cvmfs/grid.cern.ch/emi3ui-latest/etc/profile.d/setup-ui-example.sh

CMS specific area

The T2 hosts many software that are packaged with specific versions of CMSSW but that can be used in a stand alone mode. A tool was designed to easily find what is available and which versions can be used.

To list all the available software:

/swmgrs/cmss/soft.pl --list

Most used software are specific version of gcc that are needed, or a root or geant4 version. To find all the available gcc versions:

/swmgrs/cmss/soft.pl --versions gcc

Now, to get a given version of gcc (4.6.2 in this example) :

/swmgrs/cmss/soft.pl --load gcc/4.6.2

This prints the full path of the init.sh that you have to source to get the desired version of gcc :

source /cvmfs/cms.cern.ch/slc6_amd64_gcc462/external/gcc/4.6.2/etc/profile.d/init.sh

Let's now check the version of gfortran :

gfortran --version
GNU Fortran (GCC) 4.6.2