I try to install elasticsearch-6.4.2 to my cluster(HDP 3.1 Ambari 2.7.3) , intallation was completed successfully but it could not start, and the error encounterd:   Traceback (most recent call last): File "/var/lib/ambari-agent/cache/stacks/HDP/3.1/services/ELASTICSEARCH/package/scripts/es_master.py", line 168, in <module> ESMaster().execute() File "/usr/lib/ambari-agent/lib/resource_management/libraries/script/script.py", line 352, in execute method(env) File "/usr/lib/ambari-agent/lib/resource_management/libraries/script/script.py", line 1011, in restart self.start(env) File "/var/lib/ambari-agent/cache/stacks/HDP/3.1/services/ELASTICSEARCH/package/scripts/es_master.py", line 153, in start self.configure(env) File "/var/lib/ambari-agent/cache/stacks/HDP/3.1/services/ELASTICSEARCH/package/scripts/es_master.py", line 86, in configure group=params.es_group File "/usr/lib/ambari-agent/lib/resource_management/core/base.py", line 166, in __init__ self.env.run() File "/usr/lib/ambari-agent/lib/resource_management/core/environment.py", line 160, in run self.run_action(resource, action) File "/usr/lib/ambari-agent/lib/resource_management/core/environment.py", line 124, in run_action provider_action() File "/usr/lib/ambari-agent/lib/resource_management/core/providers/system.py", line 123, in action_create content = self._get_content() File "/usr/lib/ambari-agent/lib/resource_management/core/providers/system.py", line 160, in _get_content return content() File "/usr/lib/ambari-agent/lib/resource_management/core/source.py", line 52, in __call__ return self.get_content() File "/usr/lib/ambari-agent/lib/resource_management/core/source.py", line 144, in get_content rendered = self.template.render(self.context) File "/usr/lib/ambari-agent/lib/ambari_jinja2/environment.py", line 891, in render return self.environment.handle_exception(exc_info, True) File "/var/lib/ambari-agent/cache/stacks/HDP/3.1/services/ELASTICSEARCH/package/templates/elasticsearch.master.yml.j2", line 93, in top-level template code action.destructive_requires_name: {{action_destructive_requires_name}} File "/usr/lib/ambari-agent/lib/resource_management/libraries/script/config_dictionary.py", line 73, in __getattr__ raise Fail("Configuration parameter '" + self.name + "' was not found in configurations dictionary!") resource_management.core.exceptions.Fail: Configuration parameter 'hostname' was not found in configurations dictionary!   I modified the property of discovery.zen.ping.unicast.hosts from elastic-config.xml and hostname from elasticsearch-env.xml, However, it still could not start  and the same error encountered, do you have any idea? ... View more