diff --git a/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4BadRequestTests.java b/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4BadRequestTests.java
index 271afbed5d7..abd918f706b 100644
--- a/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4BadRequestTests.java
+++ b/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4BadRequestTests.java
@@ -30,6 +30,7 @@ import org.elasticsearch.common.util.MockBigArrays;
 import org.elasticsearch.common.util.MockPageCacheRecycler;
 import org.elasticsearch.common.util.concurrent.ThreadContext;
 import org.elasticsearch.http.HttpServerTransport;
+import org.elasticsearch.http.HttpTransportSettings;
 import org.elasticsearch.indices.breaker.NoneCircuitBreakerService;
 import org.elasticsearch.rest.BytesRestResponse;
 import org.elasticsearch.rest.RestChannel;
@@ -87,7 +88,8 @@ public class Netty4BadRequestTests extends ESTestCase {
             }
         };
 
-        try (HttpServerTransport httpServerTransport = new Netty4HttpServerTransport(Settings.EMPTY, networkService, bigArrays, threadPool,
+        Settings settings = Settings.builder().put(HttpTransportSettings.SETTING_HTTP_PORT.getKey(), getPortRange()).build();
+        try (HttpServerTransport httpServerTransport = new Netty4HttpServerTransport(settings, networkService, bigArrays, threadPool,
             xContentRegistry(), dispatcher, new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS),
             new SharedGroupFactory(Settings.EMPTY))) {
             httpServerTransport.start();
diff --git a/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4HttpServerTransportTests.java b/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4HttpServerTransportTests.java
index 6fb2ad01f15..8a4b5b9337b 100644
--- a/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4HttpServerTransportTests.java
+++ b/modules/transport-netty4/src/test/java/org/elasticsearch/http/netty4/Netty4HttpServerTransportTests.java
@@ -122,7 +122,7 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
      * @throws InterruptedException if the client communication with the server is interrupted
      */
     public void testExpectContinueHeader() throws InterruptedException {
-        final Settings settings = Settings.EMPTY;
+        final Settings settings = createSettings();
         final int contentLength = randomIntBetween(1, HttpTransportSettings.SETTING_HTTP_MAX_CONTENT_LENGTH.get(settings).bytesAsInt());
         runExpectHeaderTest(settings, HttpHeaderValues.CONTINUE.toString(), contentLength, HttpResponseStatus.CONTINUE);
     }
@@ -136,7 +136,7 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
     public void testExpectContinueHeaderContentLengthTooLong() throws InterruptedException {
         final String key = HttpTransportSettings.SETTING_HTTP_MAX_CONTENT_LENGTH.getKey();
         final int maxContentLength = randomIntBetween(1, 104857600);
-        final Settings settings = Settings.builder().put(key, maxContentLength + "b").build();
+        final Settings settings = createBuilderWithPort().put(key, maxContentLength + "b").build();
         final int contentLength = randomIntBetween(maxContentLength + 1, Integer.MAX_VALUE);
         runExpectHeaderTest(
                 settings, HttpHeaderValues.CONTINUE.toString(), contentLength, HttpResponseStatus.REQUEST_ENTITY_TOO_LARGE);
@@ -147,7 +147,8 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
      * @throws InterruptedException if the client communication with the server is interrupted
      */
     public void testExpectUnsupportedExpectation() throws InterruptedException {
-        runExpectHeaderTest(Settings.EMPTY, "chocolate=yummy", 0, HttpResponseStatus.EXPECTATION_FAILED);
+        Settings settings = createSettings();
+        runExpectHeaderTest(settings, "chocolate=yummy", 0, HttpResponseStatus.EXPECTATION_FAILED);
     }
 
     private void runExpectHeaderTest(
@@ -201,7 +202,8 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
     }
 
     public void testBindUnavailableAddress() {
-        try (Netty4HttpServerTransport transport = new Netty4HttpServerTransport(Settings.EMPTY, networkService, bigArrays, threadPool,
+        Settings initialSettings = createSettings();
+        try (Netty4HttpServerTransport transport = new Netty4HttpServerTransport(initialSettings, networkService, bigArrays, threadPool,
                 xContentRegistry(), new NullDispatcher(), clusterSettings, new SharedGroupFactory(Settings.EMPTY))) {
             transport.start();
             TransportAddress remoteAddress = randomFrom(transport.boundAddress().boundAddresses());
@@ -248,10 +250,10 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
         final Setting<ByteSizeValue> httpMaxInitialLineLengthSetting = HttpTransportSettings.SETTING_HTTP_MAX_INITIAL_LINE_LENGTH;
         if (randomBoolean()) {
             maxInitialLineLength = httpMaxInitialLineLengthSetting.getDefault(Settings.EMPTY).bytesAsInt();
-            settings = Settings.EMPTY;
+            settings = createSettings();
         } else {
             maxInitialLineLength = randomIntBetween(1, 8192);
-            settings = Settings.builder().put(httpMaxInitialLineLengthSetting.getKey(), maxInitialLineLength + "b").build();
+            settings = createBuilderWithPort().put(httpMaxInitialLineLengthSetting.getKey(), maxInitialLineLength + "b").build();
         }
 
         try (Netty4HttpServerTransport transport = new Netty4HttpServerTransport(
@@ -300,7 +302,7 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
 
         };
 
-        final Settings settings = Settings.builder()
+        final Settings settings = createBuilderWithPort()
             .put(SETTING_CORS_ENABLED.getKey(), true)
             .put(SETTING_CORS_ALLOW_ORIGIN.getKey(), "elastic.co").build();
 
@@ -362,7 +364,7 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
 
         };
 
-        Settings settings = Settings.builder()
+        Settings settings = createBuilderWithPort()
             .put(HttpTransportSettings.SETTING_HTTP_READ_TIMEOUT.getKey(), new TimeValue(randomIntBetween(100, 300)))
             .build();
 
@@ -396,4 +398,11 @@ public class Netty4HttpServerTransportTests extends ESTestCase {
         }
     }
 
+    private Settings createSettings() {
+        return createBuilderWithPort().build();
+    }
+
+    private Settings.Builder createBuilderWithPort() {
+        return Settings.builder().put(HttpTransportSettings.SETTING_HTTP_PORT.getKey(), getPortRange());
+    }
 }
diff --git a/plugins/transport-nio/src/test/java/org/elasticsearch/http/nio/NioHttpServerTransportTests.java b/plugins/transport-nio/src/test/java/org/elasticsearch/http/nio/NioHttpServerTransportTests.java
index 8f8d0179b35..b7b0cd7f0ed 100644
--- a/plugins/transport-nio/src/test/java/org/elasticsearch/http/nio/NioHttpServerTransportTests.java
+++ b/plugins/transport-nio/src/test/java/org/elasticsearch/http/nio/NioHttpServerTransportTests.java
@@ -113,7 +113,7 @@ public class NioHttpServerTransportTests extends ESTestCase {
      * @throws InterruptedException if the client communication with the server is interrupted
      */
     public void testExpectContinueHeader() throws InterruptedException {
-        final Settings settings = Settings.EMPTY;
+        final Settings settings = createSettings();
         final int contentLength = randomIntBetween(1, HttpTransportSettings.SETTING_HTTP_MAX_CONTENT_LENGTH.get(settings).bytesAsInt());
         runExpectHeaderTest(settings, HttpHeaderValues.CONTINUE.toString(), contentLength, HttpResponseStatus.CONTINUE);
     }
@@ -127,7 +127,7 @@ public class NioHttpServerTransportTests extends ESTestCase {
     public void testExpectContinueHeaderContentLengthTooLong() throws InterruptedException {
         final String key = HttpTransportSettings.SETTING_HTTP_MAX_CONTENT_LENGTH.getKey();
         final int maxContentLength = randomIntBetween(1, 104857600);
-        final Settings settings = Settings.builder().put(key, maxContentLength + "b").build();
+        final Settings settings = createBuilderWithPort().put(key, maxContentLength + "b").build();
         final int contentLength = randomIntBetween(maxContentLength + 1, Integer.MAX_VALUE);
         runExpectHeaderTest(
             settings, HttpHeaderValues.CONTINUE.toString(), contentLength, HttpResponseStatus.REQUEST_ENTITY_TOO_LARGE);
@@ -138,7 +138,8 @@ public class NioHttpServerTransportTests extends ESTestCase {
      * @throws InterruptedException if the client communication with the server is interrupted
      */
     public void testExpectUnsupportedExpectation() throws InterruptedException {
-        runExpectHeaderTest(Settings.EMPTY, "chocolate=yummy", 0, HttpResponseStatus.EXPECTATION_FAILED);
+        final Settings settings = createSettings();
+        runExpectHeaderTest(settings, "chocolate=yummy", 0, HttpResponseStatus.EXPECTATION_FAILED);
     }
 
     private void runExpectHeaderTest(
@@ -193,7 +194,8 @@ public class NioHttpServerTransportTests extends ESTestCase {
     }
 
     public void testBindUnavailableAddress() {
-        try (NioHttpServerTransport transport = new NioHttpServerTransport(Settings.EMPTY, networkService, bigArrays, pageRecycler,
+        final Settings initialSettings = createSettings();
+        try (NioHttpServerTransport transport = new NioHttpServerTransport(initialSettings, networkService, bigArrays, pageRecycler,
             threadPool, xContentRegistry(), new NullDispatcher(), new NioGroupFactory(Settings.EMPTY, logger),
             new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS))) {
             transport.start();
@@ -234,9 +236,10 @@ public class NioHttpServerTransportTests extends ESTestCase {
 
         };
 
-        final Settings settings = Settings.builder()
+        final Settings settings = createBuilderWithPort()
             .put(SETTING_CORS_ENABLED.getKey(), true)
-            .put(SETTING_CORS_ALLOW_ORIGIN.getKey(), "elastic.co").build();
+            .put(SETTING_CORS_ALLOW_ORIGIN.getKey(), "elastic.co")
+            .build();
 
         try (NioHttpServerTransport transport = new NioHttpServerTransport(settings, networkService, bigArrays, pageRecycler,
             threadPool, xContentRegistry(), dispatcher, new NioGroupFactory(settings, logger),
@@ -304,10 +307,10 @@ public class NioHttpServerTransportTests extends ESTestCase {
         final Setting<ByteSizeValue> httpMaxInitialLineLengthSetting = HttpTransportSettings.SETTING_HTTP_MAX_INITIAL_LINE_LENGTH;
         if (randomBoolean()) {
             maxInitialLineLength = httpMaxInitialLineLengthSetting.getDefault(Settings.EMPTY).bytesAsInt();
-            settings = Settings.EMPTY;
+            settings = createSettings();
         } else {
             maxInitialLineLength = randomIntBetween(1, 8192);
-            settings = Settings.builder().put(httpMaxInitialLineLengthSetting.getKey(), maxInitialLineLength + "b").build();
+            settings = createBuilderWithPort().put(httpMaxInitialLineLengthSetting.getKey(), maxInitialLineLength + "b").build();
         }
 
         try (NioHttpServerTransport transport = new NioHttpServerTransport(settings, networkService, bigArrays, pageRecycler,
@@ -356,7 +359,7 @@ public class NioHttpServerTransportTests extends ESTestCase {
 
         };
 
-        Settings settings = Settings.builder()
+        Settings settings = createBuilderWithPort()
             .put(HttpTransportSettings.SETTING_HTTP_READ_TIMEOUT.getKey(), new TimeValue(randomIntBetween(100, 300)))
             .build();
 
@@ -382,4 +385,11 @@ public class NioHttpServerTransportTests extends ESTestCase {
         }
     }
 
+    private Settings createSettings() {
+        return createBuilderWithPort().build();
+    }
+
+    private Settings.Builder createBuilderWithPort() {
+        return Settings.builder().put(HttpTransportSettings.SETTING_HTTP_PORT.getKey(), getPortRange());
+    }
 }