Hi Jason Are you seeing any errors in your data node logs. Specifically like ' xceivers count exceeded'. In that case you may need to bump up te value of dfs.datanode.max.xcievers to ahigher value.
If not, it is possible that you are crossing the upper limit of open files on your linux boxes that run DNs. You can verify the current value using 'ulimit -n' and then try increasing the same to a much higher value. Regards Bejoy KS
