Hi there
We plan to migrate a 30 nodes hadoop 1.0.1 cluster to the version 2.3.0. We don’t have extra machines to setup a separate new cluster, thus hope to do an “in-place” migration by replacing the components on the existing computers. So the questions are: 1) Is it possible to do an “in-place” migration, while keeping all data in HDFS safely? 2) If it is yes, is there any doc/guidance to do this? 3) Is the 2.0.3 MR API binary compatible with the one of 1.0.1? Any information are highly appreciated. Jerry Zhang