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Host not found, hostname=


At wits end wit this hortwork work platform , trying to get it kerborized.

The phase where it Testing Kerberos clients, keep getting this error that it cannot find the ambari host and displays the fqdn

The ambari host is name resolved by 2 hosted domains internally with no problem. ie and I also added this in /etc/hosts files on each server in cluster including ambari server , each maser node , slave node and DC on our network to eliminate DNS as an issue ( which I cannot believe it is as at teh command line these things can resolve all day long to each other) What logs can I examine to give more information on this error please?

var/log/ambari-server is not much help


Master Mentor

@Tom Burke

You can also open the same URL from the Browser where you have logged in the Ambari UI as well.,Hosts/host_name


(OR) You can use the following curl call to produce the JSON output to some file like "/tmp/hosts.json". Also pleas emake sure to use the correct cluster name in the same URL.

# curl -k -H "X-Requested-By: ambari" -u admin:admin ",Hosts/host_name" -o "/tmp/hosts.json"


Expert Contributor

hi @Jay Kumar SenSharma,

i am upgrading from HDP 2.6.2 to HDP 3.1, i am using Ambari and currently stuck on (generate missing principal ), my cluster is kerberized, the machine hosting ambari server doesn't have ambari agent, and i am also getting the same error (host not found) for the ambari master machine , below is the exact error from ambari server log

2019-05-07 16:55:58,023  WARN [Server Action Executor Worker 3611] ServerActionExecutor:471 - Task #3611 failed to complete execution due to thrown exception: org.apache.ambari.server.HostNotFoundException:Host not found,
org.apache.ambari.server.HostNotFoundException: Host not found,
        at org.apache.ambari.server.state.cluster.ClustersImpl.getHost(
        at org.apache.ambari.server.state.ConfigHelper.getEffectiveDesiredTags(
        at org.apache.ambari.server.state.ConfigHelper.getEffectiveDesiredTags(
        at org.apache.ambari.server.controller.AmbariManagementControllerImpl.findConfigurationTagsWithOverrides(
        at sun.reflect.GeneratedMethodAccessor424.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(
        at java.lang.reflect.Method.invoke(
        at com.sun.proxy.$Proxy131.findConfigurationTagsWithOverrides(Unknown Source)
        at org.apache.ambari.server.state.ConfigHelper.calculateExistingConfigurations(
        at org.apache.ambari.server.controller.KerberosHelperImpl.calculateConfigurations(
        at org.apache.ambari.server.controller.KerberosHelperImpl.getActiveIdentities(
        at org.apache.ambari.server.serveraction.kerberos.KerberosServerAction.calculateServiceIdentities(
        at org.apache.ambari.server.serveraction.kerberos.KerberosServerAction.processIdentities(
        at org.apache.ambari.server.serveraction.kerberos.CreatePrincipalsServerAction.execute(
        at org.apache.ambari.server.serveraction.ServerActionExecutor$Worker.execute(
        at org.apache.ambari.server.serveraction.ServerActionExecutor$

can you please suggest what to do?

Expert Contributor

@jsensharma This issue has been observed in the internal lab cluster as well.


curl -H "X-Requested-By: ambari" -u admin:pnarayanasamy""


ambari server & kdc host is not listed in the items array response.


/etc/hosts having only one fqdn for all the ip's.



Screenshot 2019-10-24 at 7.52.31 PM.png


Hi all,


I had faced the same issue while kerberizing a HDP 3.1.0 cluster integrated with Iislon.

The Ambari serer is a built on a Postgres DB cluster, hence it was NOT in the hadoop cluster.

so it was NOT on the host list.

[root@hdpdb ~]# curl -H "X-Requested-By: ambari" -u admin:admin "http://hdpdb.gz.local:8080/api/v1/clusters/Panyu/hosts"



I had to add the ambari server from adding host wizard and just install the clients.

It worked around the "Host not found, hostname= xxxx" issue in my case. 




Hope it will help, cheer!