https://community.cloudera.com/t5/Support-Questions/HeartBeat-Lost-loss-for-all-services/m-p/121163#M83926 <P>Seems IT changed domain name, updated /etc/host and resolv.conf to reflect old fqdn name.But restart cluster was failing with </P><P>Failed on local exception: java.io.IOException: java.lang.IllegalArgumentException: Server has invalid Kerberos principal: nn/mxspdh10.amdocs.com@MXSPDH10.KERBEROS.COM; Host Details : local host is: "mxspdh10.mx.amdocs.com/135.208.66.57"; destination host is: "mxspdh10.amdocs.com":8020; </P><P>Local host is .mx.amdocs.com and expected was amdocs.com.</P><P>After resolv.conf chnage ,tried rebooting cluster ,but post that facing ambari-agent heartbeat issues.Same error as shared in the forum.Suggession pls.</P> Thu, 12 May 2016 15:45:37 GMT Rajat 2016-05-12T15:45:37Z