> I have 2 nics on my datanodes, is it possible to used the one dedicated
> for replication and other for all other comunication i.e with jt and
> namenodes ?
Please correct me, I am wrong, but I have never seen a support for that in
Hadoop. DataNodes uses limited number of threads for balancing (afaik, 5
maximally + dfs.datanode.balance.bandwidthPerSec), so this way resources
used for balancing can be limited.
> Also eventhough I am using rackawareness script and dfsreport shows the
> racks jobtracker shows all tasktracker in default rack, how to correct that.
We switched to YARN recently, so it is difficult for me to check it now.
Do you have rack-awareness script deployed on the JobTracker machine?