diff --git a/buildSrc/src/main/resources/checkstyle_suppressions.xml b/buildSrc/src/main/resources/checkstyle_suppressions.xml
index 3578fab9953..51349520810 100644
--- a/buildSrc/src/main/resources/checkstyle_suppressions.xml
+++ b/buildSrc/src/main/resources/checkstyle_suppressions.xml
@@ -626,7 +626,7 @@
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]ingest[/\\]SimulatePipelineResponseTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]ingest[/\\]WriteableIngestDocumentTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]search[/\\]SearchRequestBuilderTests.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]AutoCreateIndexTests.java" checks="LineLength" />
+  <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]IndicesOptionsTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]IndicesOptionsTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]TransportActionFilterChainTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]support[/\\]WaitActiveShardCountIT.java" checks="LineLength" />
diff --git a/core/src/main/java/org/elasticsearch/action/ActionModule.java b/core/src/main/java/org/elasticsearch/action/ActionModule.java
index ca5349661c5..1be1ddda9a4 100644
--- a/core/src/main/java/org/elasticsearch/action/ActionModule.java
+++ b/core/src/main/java/org/elasticsearch/action/ActionModule.java
@@ -20,7 +20,6 @@
 package org.elasticsearch.action;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
@@ -335,7 +334,7 @@ public class ActionModule extends AbstractModule {
         this.actionPlugins = actionPlugins;
         actions = setupActions(actionPlugins);
         actionFilters = setupActionFilters(actionPlugins, ingestEnabled);
-        autoCreateIndex = transportClient ? null : new AutoCreateIndex(settings, resolver);
+        autoCreateIndex = transportClient ? null : new AutoCreateIndex(settings, clusterSettings, resolver);
         destructiveOperations = new DestructiveOperations(settings, clusterSettings);
         Set<String> headers = actionPlugins.stream().flatMap(p -> p.getRestHeaders().stream()).collect(Collectors.toSet());
         restController = new RestController(settings, headers);
diff --git a/core/src/main/java/org/elasticsearch/action/support/AutoCreateIndex.java b/core/src/main/java/org/elasticsearch/action/support/AutoCreateIndex.java
index d4ddae78225..5c9152b4751 100644
--- a/core/src/main/java/org/elasticsearch/action/support/AutoCreateIndex.java
+++ b/core/src/main/java/org/elasticsearch/action/support/AutoCreateIndex.java
@@ -24,8 +24,8 @@ import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.common.Booleans;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.collect.Tuple;
-import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.regex.Regex;
+import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.common.settings.Settings;
@@ -41,16 +41,17 @@ import java.util.List;
 public final class AutoCreateIndex {
 
     public static final Setting<AutoCreate> AUTO_CREATE_INDEX_SETTING =
-        new Setting<>("action.auto_create_index", "true", AutoCreate::new, Property.NodeScope);
+        new Setting<>("action.auto_create_index", "true", AutoCreate::new, Property.NodeScope, Setting.Property.Dynamic);
 
     private final boolean dynamicMappingDisabled;
     private final IndexNameExpressionResolver resolver;
-    private final AutoCreate autoCreate;
+    private volatile AutoCreate autoCreate;
 
-    public AutoCreateIndex(Settings settings, IndexNameExpressionResolver resolver) {
+    public AutoCreateIndex(Settings settings, ClusterSettings clusterSettings, IndexNameExpressionResolver resolver) {
         this.resolver = resolver;
         dynamicMappingDisabled = !MapperService.INDEX_MAPPER_DYNAMIC_SETTING.get(settings);
         this.autoCreate = AUTO_CREATE_INDEX_SETTING.get(settings);
+        clusterSettings.addSettingsUpdateConsumer(AUTO_CREATE_INDEX_SETTING, this::setAutoCreate);
     }
 
     /**
@@ -64,6 +65,8 @@ public final class AutoCreateIndex {
      * Should the index be auto created?
      */
     public boolean shouldAutoCreate(String index, ClusterState state) {
+        // One volatile read, so that all checks are done against the same instance:
+        final AutoCreate autoCreate = this.autoCreate;
         if (autoCreate.autoCreateIndex == false) {
             return false;
         }
@@ -87,7 +90,15 @@ public final class AutoCreateIndex {
         return false;
     }
 
-    private static class AutoCreate {
+    AutoCreate getAutoCreate() {
+        return autoCreate;
+    }
+
+    void setAutoCreate(AutoCreate autoCreate) {
+        this.autoCreate = autoCreate;
+    }
+
+    static class AutoCreate {
         private final boolean autoCreateIndex;
         private final List<Tuple<String, Boolean>> expressions;
 
@@ -128,5 +139,13 @@ public final class AutoCreateIndex {
             this.expressions = expressions;
             this.autoCreateIndex = autoCreateIndex;
         }
+
+        boolean isAutoCreateIndex() {
+            return autoCreateIndex;
+        }
+
+        List<Tuple<String, Boolean>> getExpressions() {
+            return expressions;
+        }
     }
 }
diff --git a/core/src/test/java/org/elasticsearch/action/support/AutoCreateIndexTests.java b/core/src/test/java/org/elasticsearch/action/support/AutoCreateIndexTests.java
index 9572a2df652..8a45ca47535 100644
--- a/core/src/test/java/org/elasticsearch/action/support/AutoCreateIndexTests.java
+++ b/core/src/test/java/org/elasticsearch/action/support/AutoCreateIndexTests.java
@@ -25,6 +25,7 @@ import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.cluster.metadata.MetaData;
+import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.mapper.MapperService;
 import org.elasticsearch.test.ESTestCase;
@@ -35,10 +36,12 @@ public class AutoCreateIndexTests extends ESTestCase {
 
     public void testParseFailed() {
         try {
-            new AutoCreateIndex(Settings.builder().put("action.auto_create_index", ",,,").build(), new IndexNameExpressionResolver(Settings.EMPTY));
+            Settings settings = Settings.builder().put("action.auto_create_index", ",,,").build();
+            newAutoCreateIndex(settings);
             fail("initialization should have failed");
         } catch (IllegalArgumentException ex) {
-            assertEquals("Can't parse [,,,] for setting [action.auto_create_index] must be either [true, false, or a comma separated list of index patterns]", ex.getMessage());
+            assertEquals("Can't parse [,,,] for setting [action.auto_create_index] must be either [true, false, or a " +
+                    "comma separated list of index patterns]", ex.getMessage());
         }
     }
 
@@ -46,46 +49,51 @@ public class AutoCreateIndexTests extends ESTestCase {
         String prefix = randomFrom("+", "-");
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), prefix).build();
         try {
-            new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+            newAutoCreateIndex(settings);
             fail("initialization should have failed");
         } catch(IllegalArgumentException ex) {
-            assertEquals("Can't parse [" + prefix + "] for setting [action.auto_create_index] must contain an index name after [" + prefix + "]", ex.getMessage());
+            assertEquals("Can't parse [" + prefix + "] for setting [action.auto_create_index] must contain an index name after ["
+                    + prefix + "]", ex.getMessage());
         }
     }
 
     public void testAutoCreationDisabled() {
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), false).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(Settings.EMPTY));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         assertThat(autoCreateIndex.shouldAutoCreate(randomAsciiOfLengthBetween(1, 10), buildClusterState()), equalTo(false));
     }
 
     public void testAutoCreationEnabled() {
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), true).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(Settings.EMPTY));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         assertThat(autoCreateIndex.shouldAutoCreate(randomAsciiOfLengthBetween(1, 10), buildClusterState()), equalTo(true));
     }
 
     public void testDefaultAutoCreation() {
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(Settings.EMPTY, new IndexNameExpressionResolver(Settings.EMPTY));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(Settings.EMPTY);
         assertThat(autoCreateIndex.shouldAutoCreate(randomAsciiOfLengthBetween(1, 10), buildClusterState()), equalTo(true));
     }
 
     public void testExistingIndex() {
-        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom(true, false, randomAsciiOfLengthBetween(7, 10))).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(Settings.EMPTY));
-        assertThat(autoCreateIndex.shouldAutoCreate(randomFrom("index1", "index2", "index3"), buildClusterState("index1", "index2", "index3")), equalTo(false));
+        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom(true, false,
+                randomAsciiOfLengthBetween(7, 10))).build();
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
+        assertThat(autoCreateIndex.shouldAutoCreate(randomFrom("index1", "index2", "index3"),
+                buildClusterState("index1", "index2", "index3")), equalTo(false));
     }
 
     public void testDynamicMappingDisabled() {
-        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom(true, randomAsciiOfLengthBetween(1, 10)))
+        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom(true,
+                randomAsciiOfLengthBetween(1, 10)))
             .put(MapperService.INDEX_MAPPER_DYNAMIC_SETTING.getKey(), false).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(Settings.EMPTY));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         assertThat(autoCreateIndex.shouldAutoCreate(randomAsciiOfLengthBetween(1, 10), buildClusterState()), equalTo(false));
     }
 
     public void testAutoCreationPatternEnabled() {
-        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom("+index*", "index*")).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom("+index*", "index*"))
+                .build();
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("index" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(true));
         assertThat(autoCreateIndex.shouldAutoCreate("does_not_match" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(false));
@@ -93,7 +101,7 @@ public class AutoCreateIndexTests extends ESTestCase {
 
     public void testAutoCreationPatternDisabled() {
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), "-index*").build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("index" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(false));
         //default is false when patterns are specified
@@ -101,8 +109,9 @@ public class AutoCreateIndexTests extends ESTestCase {
     }
 
     public void testAutoCreationMultiplePatternsWithWildcards() {
-        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), randomFrom("+test*,-index*", "test*,-index*")).build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(),
+                randomFrom("+test*,-index*", "test*,-index*")).build();
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("index" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(false));
         assertThat(autoCreateIndex.shouldAutoCreate("test" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(true));
@@ -111,7 +120,7 @@ public class AutoCreateIndexTests extends ESTestCase {
 
     public void testAutoCreationMultiplePatternsNoWildcards() {
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), "+test1,-index1").build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("test1", clusterState), equalTo(true));
         assertThat(autoCreateIndex.shouldAutoCreate("index" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(false));
@@ -121,7 +130,7 @@ public class AutoCreateIndexTests extends ESTestCase {
 
     public void testAutoCreationMultipleIndexNames() {
         Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), "test1,test2").build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("test1", clusterState), equalTo(true));
         assertThat(autoCreateIndex.shouldAutoCreate("test2", clusterState), equalTo(true));
@@ -129,19 +138,51 @@ public class AutoCreateIndexTests extends ESTestCase {
     }
 
     public void testAutoCreationConflictingPatternsFirstWins() {
-        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), "+test1,-test1,-test2,+test2").build();
-        AutoCreateIndex autoCreateIndex = new AutoCreateIndex(settings, new IndexNameExpressionResolver(settings));
+        Settings settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(),
+                "+test1,-test1,-test2,+test2").build();
+        AutoCreateIndex autoCreateIndex = newAutoCreateIndex(settings);
         ClusterState clusterState = ClusterState.builder(new ClusterName("test")).metaData(MetaData.builder()).build();
         assertThat(autoCreateIndex.shouldAutoCreate("test1", clusterState), equalTo(true));
         assertThat(autoCreateIndex.shouldAutoCreate("test2", clusterState), equalTo(false));
         assertThat(autoCreateIndex.shouldAutoCreate("does_not_match" + randomAsciiOfLengthBetween(1, 5), clusterState), equalTo(false));
     }
 
+    public void testUpdate() {
+        boolean value = randomBoolean();
+        Settings settings;
+        if (value && randomBoolean()) {
+            settings = Settings.EMPTY;
+        } else {
+            settings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), value).build();
+        }
+
+        ClusterSettings clusterSettings = new ClusterSettings(settings,
+                ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
+        AutoCreateIndex  autoCreateIndex = new AutoCreateIndex(settings, clusterSettings, new IndexNameExpressionResolver(settings));
+        assertThat(autoCreateIndex.getAutoCreate().isAutoCreateIndex(), equalTo(value));
+
+        Settings newSettings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), !value).build();
+        clusterSettings.applySettings(newSettings);
+        assertThat(autoCreateIndex.getAutoCreate().isAutoCreateIndex(), equalTo(!value));
+
+        newSettings = Settings.builder().put(AutoCreateIndex.AUTO_CREATE_INDEX_SETTING.getKey(), "logs-*").build();
+        clusterSettings.applySettings(newSettings);
+        assertThat(autoCreateIndex.getAutoCreate().isAutoCreateIndex(), equalTo(true));
+        assertThat(autoCreateIndex.getAutoCreate().getExpressions().size(), equalTo(1));
+        assertThat(autoCreateIndex.getAutoCreate().getExpressions().get(0).v1(), equalTo("logs-*"));
+    }
+
     private static ClusterState buildClusterState(String... indices) {
         MetaData.Builder metaData = MetaData.builder();
         for (String index : indices) {
             metaData.put(IndexMetaData.builder(index).settings(settings(Version.CURRENT)).numberOfShards(1).numberOfReplicas(1));
         }
-        return ClusterState.builder(org.elasticsearch.cluster.ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY)).metaData(metaData).build();
+        return ClusterState.builder(org.elasticsearch.cluster.ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY))
+                .metaData(metaData).build();
+    }
+
+    private AutoCreateIndex newAutoCreateIndex(Settings settings) {
+        return new AutoCreateIndex(settings, new ClusterSettings(settings,
+                ClusterSettings.BUILT_IN_CLUSTER_SETTINGS), new IndexNameExpressionResolver(settings));
     }
 }
diff --git a/core/src/test/java/org/elasticsearch/index/mapper/DynamicMappingDisabledTests.java b/core/src/test/java/org/elasticsearch/index/mapper/DynamicMappingDisabledTests.java
index 0cd6f93ba3a..111f4b470d4 100644
--- a/core/src/test/java/org/elasticsearch/index/mapper/DynamicMappingDisabledTests.java
+++ b/core/src/test/java/org/elasticsearch/index/mapper/DynamicMappingDisabledTests.java
@@ -29,6 +29,7 @@ import org.elasticsearch.cluster.action.shard.ShardStateAction;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
+import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.IndexNotFoundException;
 import org.elasticsearch.indices.IndicesService;
@@ -81,7 +82,8 @@ public class DynamicMappingDisabledTests extends ESSingleNodeTestCase {
         shardStateAction = new ShardStateAction(settings, clusterService, transportService, null, null, THREAD_POOL);
         actionFilters = new ActionFilters(Collections.emptySet());
         indexNameExpressionResolver = new IndexNameExpressionResolver(settings);
-        autoCreateIndex = new AutoCreateIndex(settings, indexNameExpressionResolver);
+        autoCreateIndex = new AutoCreateIndex(settings, new ClusterSettings(settings, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS),
+                indexNameExpressionResolver);
     }
 
     @After
diff --git a/modules/reindex/src/test/java/org/elasticsearch/index/reindex/ReindexSourceTargetValidationTests.java b/modules/reindex/src/test/java/org/elasticsearch/index/reindex/ReindexSourceTargetValidationTests.java
index 1213762155b..12ed0ed090f 100644
--- a/modules/reindex/src/test/java/org/elasticsearch/index/reindex/ReindexSourceTargetValidationTests.java
+++ b/modules/reindex/src/test/java/org/elasticsearch/index/reindex/ReindexSourceTargetValidationTests.java
@@ -31,10 +31,13 @@ import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.cluster.metadata.MetaData;
 import org.elasticsearch.common.bytes.BytesArray;
+import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.reindex.remote.RemoteInfo;
 import org.elasticsearch.test.ESTestCase;
 
+import java.util.Collections;
+
 import static java.util.Collections.emptyMap;
 import static org.hamcrest.Matchers.containsString;
 
@@ -54,7 +57,8 @@ public class ReindexSourceTargetValidationTests extends ESTestCase {
                 .put(index("source", "source_multi"), true)
                 .put(index("source2", "source_multi"), true)).build();
     private static final IndexNameExpressionResolver INDEX_NAME_EXPRESSION_RESOLVER = new IndexNameExpressionResolver(Settings.EMPTY);
-    private static final AutoCreateIndex AUTO_CREATE_INDEX = new AutoCreateIndex(Settings.EMPTY, INDEX_NAME_EXPRESSION_RESOLVER);
+    private static final AutoCreateIndex AUTO_CREATE_INDEX = new AutoCreateIndex(Settings.EMPTY,
+            new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS), INDEX_NAME_EXPRESSION_RESOLVER);
 
     public void testObviousCases() {
         fails("target", "target");