ROOT version dependent on ssh to CERN computer

I’m finding that when I ssh into CERN via the lxplus computer, the version of ROOT that starts up when commanded is ROOT v5, and the plotting macro I’m using works fine, whereas via lxplus7, which assigns me to any given computer, ROOT v6 starts up and the macro cannot run correctly. It may be that the macro is only compatible with ROOT v6, but still it’s unusual that there are two different versions of ROOT depending on what ssh you use. (Command line ssh -XY [user]@lxplus(7)

Can someone clarify this for me? I’m not the only person it happens to, either.

If your macro works with v5 and not with v6 it means it is not fully C++ compliant and some fixes are needed for v6. If you make it work with v6 it should also work with v5. Can you post it here ?

As an aside, note that it’s expected (and desired) that lxplus7 (where 7 stands for centos7) provides a more recent software stack than lxplus (which runs slc6).

However, typically you wouldn’t use the ROOT version installed in the system but you would source the ROOT version you need (and a software environment compatible with it) via the LCG releases on cmvfs, e.g. source /cvmfs/ gives you ROOT v6.14/04 on lxplus7.