On 09/11/10 18:47, Fabio A. Miranda wrote:
hello,
I am trying to setup an Hadoop cluster. From the docs, it says I need
two master: NameNode and Jobtracker and one slave: datanode,
tasktracker.
so, I need at least 4 machines to set up a cluster with hadoop ?
How can I define the role of each machine if core-site.xml needs to be
the same ?
You can put the JT on the same server as the namenode; this is something
doing in any "small" cluster, where small probably means less than 20 or
so servers.
I do virtual clusters, and make sure that the "master" node has a very
small datanode on it too (but no job tracker), as with that setup the
filesystem and the Job tracker can go live on a single VM -you only add
more virtual worker nodes to get more filesystem capacity and task trackers.
-steve
