https://community.cloudera.com/t5/Support-Questions/Kerberos-ticket-renewal-after-expiry-period/m-p/222948#M184813 <P><A href="mailto:solr/solr1.mycluster.com@MYCLUSTER.COM">solr/solr1.mycluster.com@MYCLUSTER.COM</A> is your Kerberos principal, and it is trying to connect to <A href="http://solr2.mycluster.com/172.31.16.23:8020;">solr2.mycluster.com/172.31.16.23:8020;</A>, which is servername/IP:Port. I really think this is pointing to your issue; </P><P>local host is: "java.net.UnknownHostException: <A href="http://solr1.mycluster.com:">solr1.mycluster.com:</A> <A href="http://solr1.mycluster.com:">solr1.mycluster.com:</A> System error" Here should be a server name and an IP. not an unknown host exception. Can you check your hostname setup (DNS or /etc/hosts) on the machine solr1? I.e. Open a shell and try a "ping solr1.mycluster.com"?</P><P>The ticket lifetime is 24h in your setup, and the renewal needs to take place within that period. The renew_lifetime is the maximum lifetime for the renewed ticket. </P><P>Do you get that error after aaround 24 hours or is it happening when you start the service?</P> Fri, 20 Apr 2018 05:21:32 GMT arald 2018-04-20T05:21:32Z