Excuse the typo, should be : Normally, when you change the >major< release, you need to upgrade HDFS (http://hadoop.apache.org/docs/stable/hdfs_user_guide.html#Upgrade+and+Rollback). This will happen when you switch major branches.
On Jun 14, 2013, at 12:10 PM, Alexander Alten-Lorenz <[email protected]> wrote: > Hi Björn, > >> has it ever happened that a migration of persistent data has been needed (or >> automatically executed) when updating a Hadoop installation within a >> release? If so, where could I find information regarding such needed >> migration? > > Normally, when you change the minor release, you need to upgrade HDFS > (http://hadoop.apache.org/docs/stable/hdfs_user_guide.html#Upgrade+and+Rollback). > This will happen when you switch major branches. > >> I would be interested because the runtime of such migration would probably >> depend on the amount of managed data and had to be planned. > Depends how much data you've stored. Michael has written a excellent blog > post about: > http://www.michael-noll.com/blog/2011/08/23/performing-an-hdfs-upgrade-of-an-hadoop-cluster/ > > Cheers, > Alex > > -- > Alexander Alten-Lorenz > http://mapredit.blogspot.com > German Hadoop LinkedIn Group: http://goo.gl/N8pCF > -- Alexander Alten-Lorenz http://mapredit.blogspot.com German Hadoop LinkedIn Group: http://goo.gl/N8pCF
