@Michael Sobelman That DNS is not detectable by the node you are trying to access from. You can be fancy on aws and configure through routing tables by setting up a proper vpn between the EMR and NiFi nodes. Another option I used is route53 which will give you DNS publicly available. Lastly you can put a ELB infront of your EMR HBase master node. You may have to script it up (via boot scripts) to configure your ELB to point to new internal IP. ... View more