I am also experiencing large numbers of open connections on my datanodes. using lsof I see ~23,000 open tcp connections to the datanode with status CLOSE_WAIT Restarting the cluster brings the open file descriptors down to a sane number. I believe this is being caused by https://issues.apache.org/jira/browse/HDFS-5671   Is cloudera aware of this? Any timeline on when it will be patched into CDH?       ... View more