diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowReactiveWebServerFactory.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowReactiveWebServerFactory.java
index 9faacf0992..27348dd0b1 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowReactiveWebServerFactory.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowReactiveWebServerFactory.java
@@ -141,6 +141,7 @@ public class UndertowReactiveWebServerFactory extends AbstractReactiveWebServerF
 		else {
 			builder.addHttpListener(port, getListenAddress());
 		}
+		builder.setServerOption(UndertowOptions.SHUTDOWN_TIMEOUT, 0);
 		for (UndertowBuilderCustomizer customizer : this.builderCustomizers) {
 			customizer.customize(builder);
 		}
diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowServletWebServerFactory.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowServletWebServerFactory.java
index 161c2d1f52..dc5813bb04 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowServletWebServerFactory.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowServletWebServerFactory.java
@@ -241,6 +241,7 @@ public class UndertowServletWebServerFactory extends AbstractServletWebServerFac
 		else {
 			builder.addHttpListener(port, getListenAddress());
 		}
+		builder.setServerOption(UndertowOptions.SHUTDOWN_TIMEOUT, 0);
 		for (UndertowBuilderCustomizer customizer : this.builderCustomizers) {
 			customizer.customize(builder);
 		}
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java
index 6bad7271c3..6f73447206 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java
@@ -25,6 +25,7 @@ import java.time.Duration;
 import java.util.Arrays;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.BrokenBarrierException;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Future;
@@ -423,6 +424,25 @@ public abstract class AbstractReactiveWebServerFactoryTests {
 		assertThat(responseLatch.await(5, TimeUnit.SECONDS)).isTrue();
 	}
 
+	@Test
+	void whenARequestIsActiveThenStopWillComplete() throws InterruptedException, BrokenBarrierException {
+		AbstractReactiveWebServerFactory factory = getFactory();
+		BlockingHandler blockingHandler = new BlockingHandler();
+		this.webServer = factory.getWebServer(blockingHandler);
+		this.webServer.start();
+		Mono<ResponseEntity<Void>> request = getWebClient(this.webServer.getPort()).build().get().retrieve()
+				.toBodilessEntity();
+		AtomicReference<ResponseEntity<Void>> responseReference = new AtomicReference<>();
+		CountDownLatch responseLatch = new CountDownLatch(1);
+		request.subscribe((response) -> {
+			responseReference.set(response);
+			responseLatch.countDown();
+		});
+		blockingHandler.awaitQueue();
+		this.webServer.stop();
+		blockingHandler.completeOne();
+	}
+
 	protected WebClient prepareCompressionTest() {
 		Compression compression = new Compression();
 		compression.setEnabled(true);
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java
index 8f37a1fa93..b7e0042516 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java
@@ -1147,6 +1147,25 @@ public abstract class AbstractServletWebServerFactoryTests {
 		assertThat(request.get(30, TimeUnit.SECONDS)).isInstanceOf(HttpResponse.class);
 	}
 
+	@Test
+	void whenARequestIsActiveThenStopWillComplete() throws InterruptedException, BrokenBarrierException {
+		AbstractServletWebServerFactory factory = getFactory();
+		BlockingServlet blockingServlet = new BlockingServlet();
+		this.webServer = factory
+				.getWebServer((context) -> context.addServlet("blockingServlet", blockingServlet).addMapping("/"));
+		this.webServer.start();
+		int port = this.webServer.getPort();
+		initiateGetRequest(port, "/");
+		blockingServlet.awaitQueue();
+		this.webServer.stop();
+		try {
+			blockingServlet.admitOne();
+		}
+		catch (RuntimeException ex) {
+
+		}
+	}
+
 	protected Future<Boolean> initiateGracefulShutdown() {
 		RunnableFuture<Boolean> future = new FutureTask<Boolean>(() -> this.webServer.shutDownGracefully());
 		new Thread(future).start();
@@ -1524,7 +1543,10 @@ public abstract class AbstractServletWebServerFactoryTests {
 
 		public void admitOne() {
 			try {
-				this.barriers.take().await();
+				CyclicBarrier barrier = this.barriers.take();
+				if (!barrier.isBroken()) {
+					barrier.await();
+				}
 			}
 			catch (InterruptedException ex) {
 				Thread.currentThread().interrupt();