diff --git a/java/com/google/gerrit/sshd/NoShell.java b/java/com/google/gerrit/sshd/NoShell.java
index dd31e4c..2a29a62 100644
--- a/java/com/google/gerrit/sshd/NoShell.java
+++ b/java/com/google/gerrit/sshd/NoShell.java
@@ -27,10 +27,14 @@
 import java.io.OutputStream;
 import java.net.MalformedURLException;
 import java.net.URL;
+import org.apache.sshd.common.io.IoInputStream;
+import org.apache.sshd.common.io.IoOutputStream;
+import org.apache.sshd.common.util.buffer.ByteArrayBuffer;
 import org.apache.sshd.server.Environment;
 import org.apache.sshd.server.ExitCallback;
 import org.apache.sshd.server.SessionAware;
 import org.apache.sshd.server.channel.ChannelSession;
+import org.apache.sshd.server.command.AsyncCommand;
 import org.apache.sshd.server.command.Command;
 import org.apache.sshd.server.session.ServerSession;
 import org.apache.sshd.server.shell.ShellFactory;
@@ -56,13 +60,19 @@
     return shell.get();
   }
 
-  static class SendMessage implements Command, SessionAware {
+  /**
+   * When AsyncCommand is implemented by a command as below, the usual blocking streams aren't set.
+   *
+   * @see org.apache.sshd.server.command.AsyncCommand
+   */
+  static class SendMessage implements AsyncCommand, SessionAware {
     private final Provider<MessageFactory> messageFactory;
     private final SshScope sshScope;
 
-    private InputStream in;
-    private OutputStream out;
-    private OutputStream err;
+    private IoInputStream in;
+    private IoOutputStream out;
+    private IoOutputStream err;
+
     private ExitCallback exit;
     private Context context;
 
@@ -73,21 +83,36 @@
     }
 
     @Override
-    public void setInputStream(InputStream in) {
+    public void setIoInputStream(IoInputStream in) {
       this.in = in;
     }
 
     @Override
-    public void setOutputStream(OutputStream out) {
+    public void setIoOutputStream(IoOutputStream out) {
       this.out = out;
     }
 
     @Override
-    public void setErrorStream(OutputStream err) {
+    public void setIoErrorStream(IoOutputStream err) {
       this.err = err;
     }
 
     @Override
+    public void setInputStream(InputStream in) {
+      // ignored
+    }
+
+    @Override
+    public void setOutputStream(OutputStream out) {
+      // ignore
+    }
+
+    @Override
+    public void setErrorStream(OutputStream err) {
+      // ignore
+    }
+
+    @Override
     public void setExitCallback(ExitCallback callback) {
       this.exit = callback;
     }
@@ -107,8 +132,7 @@
       } finally {
         sshScope.set(old);
       }
-      err.write(Constants.encode(message));
-      err.flush();
+      err.writePacket(new ByteArrayBuffer(Constants.encode(message)));
 
       in.close();
       out.close();
diff --git a/javatests/com/google/gerrit/integration/ssh/BUILD b/javatests/com/google/gerrit/integration/ssh/BUILD
index dc8e68c..412aad8 100644
--- a/javatests/com/google/gerrit/integration/ssh/BUILD
+++ b/javatests/com/google/gerrit/integration/ssh/BUILD
@@ -5,3 +5,9 @@
     group = "peer-keys-auth",
     labels = ["ssh"],
 )
+
+acceptance_tests(
+    srcs = ["NoShellIT.java"],
+    group = "no-shell",
+    labels = ["ssh"],
+)
diff --git a/javatests/com/google/gerrit/integration/ssh/NoShellIT.java b/javatests/com/google/gerrit/integration/ssh/NoShellIT.java
new file mode 100644
index 0000000..ccaf085
--- /dev/null
+++ b/javatests/com/google/gerrit/integration/ssh/NoShellIT.java
@@ -0,0 +1,96 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.integration.ssh;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.gerrit.acceptance.GerritServer.TestSshServerAddress;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.StandaloneSiteTest;
+import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.extensions.api.GerritApi;
+import com.google.inject.Inject;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import org.junit.Test;
+
+@NoHttpd
+@UseSsh
+public class NoShellIT extends StandaloneSiteTest {
+  private static final String[] SSH_KEYGEN_CMD =
+      new String[] {"ssh-keygen", "-t", "rsa", "-q", "-P", "", "-f"};
+
+  @Inject private GerritApi gApi;
+  @Inject private @TestSshServerAddress InetSocketAddress sshAddress;
+
+  private String identityPath;
+
+  @Test(timeout = 30000)
+  public void verifyCommandsIsClosed() throws Exception {
+    try (ServerContext ctx = startServer()) {
+      setUpTestHarness(ctx);
+
+      IOException thrown = assertThrows(IOException.class, () -> execute(cmd()));
+      assertThat(thrown)
+          .hasMessageThat()
+          .contains("Hi Administrator, you have successfully connected over SSH.");
+    }
+  }
+
+  private void setUpTestHarness(ServerContext ctx) throws Exception {
+    ctx.getInjector().injectMembers(this);
+    setUpAuthentication();
+    identityPath = sitePaths.data_dir.resolve(String.format("id_rsa_%s", "admin")).toString();
+  }
+
+  private void setUpAuthentication() throws Exception {
+    execute(
+        ImmutableList.<String>builder()
+            .add(SSH_KEYGEN_CMD)
+            .add(String.format("id_rsa_%s", "admin"))
+            .build());
+    gApi.accounts()
+        .id("admin")
+        .addSshKey(
+            new String(
+                java.nio.file.Files.readAllBytes(
+                    sitePaths.data_dir.resolve(String.format("id_rsa_%s.pub", "admin"))),
+                UTF_8));
+  }
+
+  private ImmutableList<String> cmd() {
+    return ImmutableList.<String>builder()
+        .add("ssh")
+        .add("-tt")
+        .add("-o")
+        .add("StrictHostKeyChecking=no")
+        .add("-o")
+        .add("UserKnownHostsFile=/dev/null")
+        .add("-p")
+        .add(String.valueOf(sshAddress.getPort()))
+        .add("admin@" + sshAddress.getHostName())
+        .add("-i")
+        .add(identityPath)
+        .build();
+  }
+
+  private String execute(ImmutableList<String> cmd) throws Exception {
+    return execute(cmd, sitePaths.data_dir.toFile(), ImmutableMap.of());
+  }
+}