diff --git a/lib/perfdata/perfdatawriterconnection.cpp b/lib/perfdata/perfdatawriterconnection.cpp
index 46000c28f..8b50f061a 100644
--- a/lib/perfdata/perfdatawriterconnection.cpp
+++ b/lib/perfdata/perfdatawriterconnection.cpp
@@ -62,11 +62,11 @@ bool PerfdataWriterConnection::IsStopped() const
 
 void PerfdataWriterConnection::Disconnect()
 {
-	if (m_Stopped.exchange(true, std::memory_order_relaxed)) {
+	if (m_Stopped.exchange(true)) {
 		return;
 	}
 
-	std::promise<void> promise;
+	SyncResult<void> ret;
 
 	IoEngine::SpawnCoroutine(m_Strand, [&](boost::asio::yield_context yc) {
 		try {
@@ -76,9 +76,13 @@ void PerfdataWriterConnection::Disconnect()
 			 * completion.
 			 */
 			std::visit(
-				[](const auto& stream) {
+				[&](const auto& stream) {
 					if (stream->lowest_layer().is_open()) {
-						stream->lowest_layer().cancel();
+						if (m_Connected) {
+							stream->lowest_layer().cancel();
+						} else {
+							stream->lowest_layer().close();
+						}
 					}
 				},
 				m_Stream
@@ -86,13 +90,13 @@ void PerfdataWriterConnection::Disconnect()
 			m_ReconnectTimer.cancel();
 
 			Disconnect(std::move(yc));
-			promise.set_value();
+			ret.SetValue();
 		} catch (const std::exception& ex) {
-			promise.set_exception(std::current_exception());
+			ret.SetException(std::current_exception());
 		}
 	});
 
-	promise.get_future().get();
+	ret.Get();
 }
 
 AsioTlsOrTcpStream PerfdataWriterConnection::MakeStream() const
@@ -133,6 +137,10 @@ void PerfdataWriterConnection::EnsureConnected(const boost::asio::yield_context&
 			::Connect(stream->lowest_layer(), m_Host, m_Port, yc);
 
 			if constexpr (std::is_same_v<std::decay_t<decltype(stream)>, Shared<AsioTlsStream>::Ptr>) {
+				if (m_Stopped) {
+					BOOST_THROW_EXCEPTION(Stopped{});
+				}
+
 				using type = boost::asio::ssl::stream_base::handshake_type;
 
 				stream->next_layer().async_handshake(type::client, yc);
@@ -156,7 +164,7 @@ void PerfdataWriterConnection::EnsureConnected(const boost::asio::yield_context&
 
 void PerfdataWriterConnection::Disconnect(boost::asio::yield_context yc)
 {
-	if (!m_Connected.exchange(false, std::memory_order_relaxed)) {
+	if (!m_Connected.exchange(false)) {
 		return;
 	}
 
@@ -165,8 +173,9 @@ void PerfdataWriterConnection::Disconnect(boost::asio::yield_context yc)
 			if constexpr (std::is_same_v<std::decay_t<decltype(stream)>, Shared<AsioTlsStream>::Ptr>) {
 				stream->GracefulDisconnect(m_Strand, yc);
 			} else {
-				stream->lowest_layer().shutdown(boost::asio::socket_base::shutdown_both);
-				stream->lowest_layer().close();
+				boost::system::error_code ec;
+				stream->lowest_layer().shutdown(boost::asio::socket_base::shutdown_both, ec);
+				stream->lowest_layer().close(ec);
 			}
 		},
 		m_Stream
diff --git a/lib/perfdata/perfdatawriterconnection.hpp b/lib/perfdata/perfdatawriterconnection.hpp
index 729878a29..9f91f037e 100644
--- a/lib/perfdata/perfdatawriterconnection.hpp
+++ b/lib/perfdata/perfdatawriterconnection.hpp
@@ -10,6 +10,7 @@
 #include <boost/beast/http/message.hpp>
 #include <boost/beast/http/string_body.hpp>
 #include <future>
+#include <utility>
 
 namespace icinga {
 
@@ -21,6 +22,56 @@ class PerfdataWriterConnection final : public Object
 	static constexpr auto InitialRetryWait = 50ms;
 	static constexpr auto FinalRetryWait = 32s;
 
+	template<typename T>
+	class SyncResult
+	{
+		using ValueType = std::variant<std::monostate, std::conditional_t<std::is_void_v<T>, bool, T>, std::exception_ptr>;
+
+	public:
+		template<typename U, typename V = T, typename = std::enable_if_t<!std::is_void_v<V>>>
+		void SetValue(U&& v)
+		{
+			std::lock_guard lock(m_Mutex);
+			m_Value = std::forward<U>(v);
+			m_Cv.notify_one();
+		}
+
+		template<typename V = T, typename = std::enable_if_t<std::is_void_v<V>>>
+		void SetValue()
+		{
+			std::lock_guard lock(m_Mutex);
+			m_Value = true;
+			m_Cv.notify_one();
+		}
+
+		void SetException(std::exception_ptr ep)
+		{
+			std::lock_guard lock(m_Mutex);
+			m_Value = ValueType{ep};
+			m_Cv.notify_one();
+		}
+
+		T Get()
+		{
+			std::unique_lock l(m_Mutex);
+			m_Cv.wait(l, [&] { return !std::holds_alternative<std::monostate>(m_Value); });
+			if (std::holds_alternative<std::exception_ptr>(m_Value)) {
+				std::rethrow_exception(std::get<std::exception_ptr>(m_Value));
+			}
+
+			if constexpr (std::is_void_v<T>) {
+				return;
+			} else {
+				return std::move(std::get<T>(m_Value));
+			}
+		}
+
+	private:
+		std::mutex m_Mutex;
+		std::condition_variable m_Cv;
+		ValueType m_Value;
+	};
+
 public:
 	DECLARE_PTR_TYPEDEFS(PerfdataWriterConnection);
 
@@ -66,7 +117,7 @@ public:
 		}
 
 		using RetType = decltype(WriteMessage(std::declval<Buffer>(), std::declval<boost::asio::yield_context>()));
-		std::promise<RetType> promise;
+		SyncResult<RetType> ret;
 
 		IoEngine::SpawnCoroutine(m_Strand, [&](boost::asio::yield_context yc) {
 			while (true) {
@@ -75,16 +126,16 @@ public:
 
 					if constexpr (std::is_void_v<RetType>) {
 						WriteMessage(std::forward<Buffer>(buf), yc);
-						promise.set_value();
+						ret.SetValue();
 					} else {
-						promise.set_value(WriteMessage(std::forward<Buffer>(buf), yc));
+						ret.SetValue(WriteMessage(std::forward<Buffer>(buf), yc));
 					}
 
 					m_RetryTimeout = InitialRetryWait;
 					return;
 				} catch (const std::exception& ex) {
 					if (m_Stopped) {
-						promise.set_exception(std::make_exception_ptr(Stopped{}));
+						ret.SetException(std::make_exception_ptr(Stopped{}));
 						return;
 					}
 
@@ -98,14 +149,14 @@ public:
 					try {
 						BackoffWait(yc);
 					} catch (const std::exception&) {
-						promise.set_exception(std::make_exception_ptr(Stopped{}));
+						ret.SetException(std::make_exception_ptr(Stopped{}));
 						return;
 					}
 				}
 			}
 		});
 
-		return promise.get_future().get();
+		return ret.Get();
 	}
 
 	void Disconnect();
diff --git a/test/perfdata-perfdatatargetfixture.hpp b/test/perfdata-perfdatatargetfixture.hpp
index bac1c504d..8c2a381bc 100644
--- a/test/perfdata-perfdatatargetfixture.hpp
+++ b/test/perfdata-perfdatatargetfixture.hpp
@@ -71,11 +71,20 @@ public:
 		BOOST_REQUIRE(stream->next_layer().IsVerifyOK());
 	}
 
-	void Shutdown()
+	void Shutdown(bool wait = false)
 	{
 		BOOST_REQUIRE(std::holds_alternative<Shared<AsioTlsStream>::Ptr>(m_Stream));
 		auto& stream = std::get<Shared<AsioTlsStream>::Ptr>(m_Stream);
 		try {
+			if (wait) {
+				std::array<std::byte, 128> buf{};
+				boost::asio::mutable_buffer readBuf (buf.data(), buf.size());
+				boost::system::error_code ec;
+
+				do {
+					stream->read_some(readBuf, ec);
+				} while (!ec);
+			}
 			stream->next_layer().shutdown();
 		} catch (const std::exception& ex) {
 			if (const auto* se = dynamic_cast<const boost::system::system_error*>(&ex);
diff --git a/test/perfdata-perfdatawriterconnection.cpp b/test/perfdata-perfdatawriterconnection.cpp
index 16ed299a9..0f2435198 100644
--- a/test/perfdata-perfdatawriterconnection.cpp
+++ b/test/perfdata-perfdatawriterconnection.cpp
@@ -207,7 +207,7 @@ BOOST_AUTO_TEST_CASE(stuck_reading_response)
 		requestReadPromise.set_value();
 		// Do not send a response but react to the shutdown to be polite.
 		shutdownPromise.get_future().get();
-		Shutdown();
+		Shutdown(true);
 	}};
 
 	TestThread timeoutThread{[&]() {
@@ -315,7 +315,7 @@ BOOST_AUTO_TEST_CASE(http_send_retry)
 
 		SendResponse();
 
-		Shutdown();
+		Shutdown(true);
 	}};
 
 	boost::beast::http::request<boost::beast::http::string_body> request{boost::beast::http::verb::post, "foo", 10};