diff --git a/tests/ci/host_test.sh b/tests/ci/host_test.sh
index ef143f90e1..44d7517be0 100755
--- a/tests/ci/host_test.sh
+++ b/tests/ci/host_test.sh
@@ -13,7 +13,8 @@ for i in ../../libraries/ESP8266WiFi/examples/WiFiClient/WiFiClient \
 	../../libraries/ESP8266WebServer/examples/HelloServer/HelloServer \
 	../../libraries/SD/examples/Files/Files \
 	../../libraries/LittleFS/examples/LittleFS_Timestamp/LittleFS_Timestamp \
-	../../libraries/LittleFS/examples/SpeedTest/SpeedTest ; do
+	../../libraries/LittleFS/examples/SpeedTest/SpeedTest \
+	../../libraries/DNSServer/examples/DNSServer/DNSServer ; do
 	make -j2 D=1 FORCE32=0 $i
 	valgrind --leak-check=full --track-origins=yes --error-limit=no --show-leak-kinds=all --error-exitcode=999 bin/$(basename $i)/$(basename $i) -1
 done
diff --git a/tests/host/common/ArduinoMain.cpp b/tests/host/common/ArduinoMain.cpp
index 80e0a0c85b..ca03af9ddd 100644
--- a/tests/host/common/ArduinoMain.cpp
+++ b/tests/host/common/ArduinoMain.cpp
@@ -163,6 +163,7 @@ static struct option options[] = {
 
 void cleanup()
 {
+    mock_stop_udp();
     mock_stop_spiffs();
     mock_stop_littlefs();
     mock_stop_uart();
diff --git a/tests/host/common/ArduinoMainUdp.cpp b/tests/host/common/ArduinoMainUdp.cpp
index cfcaacef2a..49d7c091d2 100644
--- a/tests/host/common/ArduinoMainUdp.cpp
+++ b/tests/host/common/ArduinoMainUdp.cpp
@@ -33,7 +33,7 @@
 #include <poll.h>
 #include <map>
 
-std::map<int, UdpContext*> udps;
+static std::map<int, UdpContext*> udps;
 
 void register_udp(int sock, UdpContext* udp)
 {
@@ -58,3 +58,8 @@ void check_incoming_udp()
         }
     }
 }
+
+void mock_stop_udp()
+{
+    udps.clear();
+}
diff --git a/tests/host/common/mock.h b/tests/host/common/mock.h
index a8dc3e2bdc..dbcb1dbf31 100644
--- a/tests/host/common/mock.h
+++ b/tests/host/common/mock.h
@@ -170,6 +170,7 @@ void   mockUDPSwallow(size_t copied, char* ccinbuf, size_t& ccinbufsize);
 
 class UdpContext;
 void register_udp(int sock, UdpContext* udp = nullptr);
+void mock_stop_udp();
 
 //