Hi all, FYI, Andrew Wang (the release manager for Hadoop 3) is keeping updates on this wiki page <https://cwiki.apache.org/confluence/display/HADOOP/Hadoop+3.0.0+release>, for those who are interested.
Alpha 2 was released about a week ago. There's going to be an Alpha 3, and then a Beta 1. After that, we'll have GA, which is currently targeting July. We've seen two issues so far with Hadoop 3: 1. Hadoop 3 no longer issues delegation tokens in non-secure clusters ( YARN-4126 <https://issues.apache.org/jira/browse/YARN-4126>). I believe this has been reverted in Alpha 2 via YARN-5882 <https://issues.apache.org/jira/browse/YARN-5882>. 2. Hadoop 3 no longer allows duplicate filenames in the distributed cache, even if they're the same file. We had a problem like this long ago in Hadoop 2.0.2-alpha (see OOZIE-1089 <https://issues.apache.org/jira/browse/OOZIE-1089>), but the workaround for that doesn't seem to work here. I believe we're still hitting this issue. I imagine that Oozie 5 will be the first release that will support Hadoop 2 and Hadoop 3, so we should keep an eye on the Hadoop 3 progress. - Robert