when im trying to upgrade from 5.6 to 6.x im getting some errors im trying to do a rolling upgrade
below i have given the error which im getting even though i havent installed any plugins
[2018-06-27T05:48:38,655][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [transport-netty4]
[2018-06-27T05:48:38,655][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [tribe]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-core]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-deprecation]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-graph]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-logstash]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-ml]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-monitoring]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-rollup]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-security]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-sql]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-upgrade]
[2018-06-27T05:48:38,656][INFO ][o.e.p.PluginsService ] [es01_node] loaded module [x-pack-watcher]
[2018-06-27T05:48:38,657][INFO ][o.e.p.PluginsService ] [es01_node] no plugins loaded
[2018-06-27T05:48:42,118][ERROR][o.e.b.Bootstrap ] Exception
java.lang.IllegalArgumentException: unknown setting [path.conf] please check that any required plugins are installed, or check the breaking changes documentation for removed settings
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:344) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:308) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:282) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.SettingsModule.(SettingsModule.java:135) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.node.Node.(Node.java:339) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.node.Node.(Node.java:252) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap$5.(Bootstrap.java:213) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:213) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:326) [elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:136) [elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:127) [elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) [elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) [elasticsearch-cli-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.Command.main(Command.java:90) [elasticsearch-cli-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:93) [elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:86) [elasticsearch-6.3.0.jar:6.3.0]
[2018-06-27T05:48:42,125][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [es01_node] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.IllegalArgumentException: unknown setting [path.conf] please check that any required plugins are installed, or check the breaking changes documentation for removed settings
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:140) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:127) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.3.0.jar:6.3.0]
at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:93) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:86) ~[elasticsearch-6.3.0.jar:6.3.0]
Caused by: java.lang.IllegalArgumentException: unknown setting [path.conf] please check that any required plugins are installed, or check the breaking changes documentation for removed settings
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:344) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:308) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.AbstractScopedSettings.validate(AbstractScopedSettings.java:282) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.common.settings.SettingsModule.(SettingsModule.java:135) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.node.Node.(Node.java:339) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.node.Node.(Node.java:252) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap$5.(Bootstrap.java:213) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:213) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:326) ~[elasticsearch-6.3.0.jar:6.3.0]
at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:136) ~[elasticsearch-6.3.0.jar:6.3.0]