There are a series of scripts, with some named <script>v2.sh e.g. server/clusterinstallv2.sh
Looking at them, both refer to hadoop 0.20.2 -- so it's not having to do with MRV2 which is in the 0.23.X branch. so then what does the v2 actually mean?
Secondary question: is it (a) possible (b) advisable to use v2 versus the standard and (c) under what configuration and/or workload scenarios? If so, are there are instructions on how to do it?