RedHat
The StAB cluster subscribes to Red Hat, and uses version 6, which is one behind the latest version, version 7.
Being one version behind is typicaly not a problem, as it continues to be fully supported. However, there are software packages that like to use the bleeding edge, and there are admitted problems installing these programs.
Installation of devtoolset-2
Problems
outdated repomd.xml warnings
You can get rid of them (i.e. update the repomd.xml) by:
yum clean all yum update yum*