, As I stated initially, you need to make sure the data nodes are reachable from the SAS client.  This is one of the few reasons you would see this type of issue.  I can think of three reasons this type of issue can occur: 1. Sticky bit on /tmp, or HDFS_TEMP location is not writable for any other reason. 2. The data nodes are not reachable from the SAS client, by IP address and port, or by hostname if dfs.datanode.use.datanode.hostname is set in hdfs config 3. The namenode needs to be re-formatted as the configuration of the datanodes has changed or has otherwise been corrupted in some manner ... View more