It seems there's such a solution in 0.21, let's see how it integrates with 0.20.203
https://issues.apache.org/jira/browse/HDFS-385 http://hadoopblog.blogspot.com/2009/09/hdfs-block-replica-placement-in-your.html Do you have any hint about the release date of the stable 0.21th version? Vincent Le Thursday 06 October 2011, Will Maier a écrit : > Hi Vincent- > > On Thu, Oct 06, 2011 at 11:19:20AM +0200, Vincent Boucher wrote: > > We are wondering if it is possible to require that the namenode redirects > > the blocks of the files of a given directory to a particular set of > > datanodes? > > > > Our case is the following: > > > > - Servers > > 10 x mass storage servers of each 50TB, RAID6 > > -> 500TB available for hdfs > > 30 x working nodes with 6TB (no RAID) > > -> 180TB available for hdfs > > > > We'd like that the files stored in > > /hdfs/ms > > be hosted on the mass storage (ms) servers, > > while the files in > > /hdfs/wn > > be hosted on the working nodes (wn). > > Why do you want to partition your datanodes this way? In our cluster, > datanode size ranges from ~1 TB (no RAID) up to ~80TB (RAID). While in an > ideal world all datanodes would be similar in configuration, we have not > observed any issues with this arrangement in production.
