Thanks all for the answers!! On Thu, Mar 1, 2012 at 5:52 PM, Arpit Gupta <ar...@hortonworks.com> wrote:
> It is initiated by the slave. > > If you have defined files to state which slaves can talk to the namenode > (using config dfs.hosts) and which hosts cannot (using > property dfs.hosts.exclude) then you would need to edit these files and > issue the refresh command. > > > On Mar 1, 2012, at 5:35 PM, Mohit Anchlia wrote: > > On Thu, Mar 1, 2012 at 4:57 PM, Joey Echeverria <j...@cloudera.com> > wrote: > > Not quite. Datanodes get the namenode host from fs.defalt.name in > > core-site.xml. Task trackers find the job tracker from the > > mapred.job.tracker setting in mapred-site.xml. > > > > I actually meant to ask how does namenode/jobtracker know there is a new > node in the cluster. Is it initiated by namenode when slave file is edited? > Or is it initiated by tasktracker when tasktracker is started? > > > Sent from my iPhone > > > On Mar 1, 2012, at 18:49, Mohit Anchlia <mohitanch...@gmail.com> wrote: > > > On Thu, Mar 1, 2012 at 4:46 PM, Joey Echeverria <j...@cloudera.com> > > wrote: > > > You only have to refresh nodes if you're making use of an allows file. > > > Thanks does it mean that when tasktracker/datanode starts up it > > communicates with namenode using master file? > > > Sent from my iPhone > > > On Mar 1, 2012, at 18:29, Mohit Anchlia <mohitanch...@gmail.com> wrote: > > > Is this the right procedure to add nodes? I took some from hadoop wiki > > FAQ: > > > http://wiki.apache.org/hadoop/FAQ > > > 1. Update conf/slave > > 2. on the slave nodes start datanode and tasktracker > > 3. hadoop balancer > > > Do I also need to run dfsadmin -refreshnodes? > > > > > > -- > Arpit > Hortonworks, Inc. > email: ar...@hortonworks.com > > <http://www.hadoopsummit.org/> > <http://www.hadoopsummit.org/> > <http://www.hadoopsummit.org/> >
