I installed the latest version of ROOT (5.34-17) and the C++ analyzer (1.5.25) in the 64-bit /adaqfs/apps directory. It will be automatically picked up by all accounts logging into adaq1/2 and aonl1/2/3 UNLESS some login script explicitly sets ROOTSYS, LD_LIBRARY_PATH etc. I've made sure that the a-onl account works.
The 32-bit version has not yet been updated. I'll leave it alone for now. (You can't see the 32-bit version from the 64-bit machines.)
If you have any custom libraries for 64-bit, you must recompile them. Same for compiled scripts. I realize this might cause a few small hiccups. The old 64-bit ROOT version (5.30-6) is now under /adaqfs/apps/ROOT/old.
Ole