https://community.cloudera.com/t5/Support-Questions/FQDN-is-not-set-for-hosts-Any-issues-in-prod-environment/m-p/208932#M170889 <P><EM><A href="https://community.hortonworks.com/questions/194517/@Sriram">@Sriram</A></EM></P><P><EM>Extract for the <A href="https://ambari.apache.org/1.2.4/installing-hadoop-using-ambari/content/ambari-chap1-5-4.html" target="_blank"> Hortonworks documentation</A><BR /></EM><I><STRONG><BR /></STRONG></I></P><P><I><STRONG>"All hosts in your system must be configured for DNS and Reverse DNS."</STRONG></I><EM><BR /></EM></P><P><EM>If you are unable to configure DNS and Reverse DNS, you must edit the hosts' file on every host in your cluster to contain the address of each of your hosts and to set the Fully Qualified Domain Name hostname of each of those hosts. </EM></P><P><EM>So that clearly answers your worries <span class="lia-unicode-emoji" title=":slightly_smiling_face:">🙂</span></EM></P><P><EM>HTH</EM></P> Wed, 06 Jun 2018 14:48:53 GMT Shelton 2018-06-06T14:48:53Z