diff --git a/modules/mqtt/testcontainers/mqtt/__init__.py b/modules/mqtt/testcontainers/mqtt/__init__.py
index 54a2d87ac..18a1e1917 100644
--- a/modules/mqtt/testcontainers/mqtt/__init__.py
+++ b/modules/mqtt/testcontainers/mqtt/__init__.py
@@ -121,6 +121,10 @@ def start(self, configfile: Optional[str] = None) -> Self:
             # default config file
             configfile = Path(__file__).parent / MosquittoContainer.CONFIG_FILE
         self.with_volume_mapping(configfile, "/mosquitto/config/mosquitto.conf")
+        # since version 2.1.1 - 2026-02-04, which fixed a PUID/PGID issue, the container needs to write to the data directory, 
+        # so we need to map it to a volume
+        self.with_volume_mapping("mosquitto_data", "/data", mode="rw")
+
         # if self.password:
         #     # TODO: add authentication
         #     pass
diff --git a/modules/mqtt/testcontainers/mqtt/testcontainers-mosquitto-default-configuration.conf b/modules/mqtt/testcontainers/mqtt/testcontainers-mosquitto-default-configuration.conf
index 13728cec0..b3c67048f 100644
--- a/modules/mqtt/testcontainers/mqtt/testcontainers-mosquitto-default-configuration.conf
+++ b/modules/mqtt/testcontainers/mqtt/testcontainers-mosquitto-default-configuration.conf
@@ -1,7 +1,6 @@
 # see https://mosquitto.org/man/mosquitto-conf-5.html
 
-protocol mqtt
-user root
+listener 1883
 log_dest stdout
 allow_anonymous true
 
@@ -14,7 +13,4 @@ log_timestamp_format %Y-%m-%d %H:%M:%S
 persistence true
 persistence_location /data/
 
-listener 1883
-protocol mqtt
-
 sys_interval 1
diff --git a/modules/mqtt/tests/test_mosquitto.py b/modules/mqtt/tests/test_mosquitto.py
index 63ce7fcd9..29ce1443f 100644
--- a/modules/mqtt/tests/test_mosquitto.py
+++ b/modules/mqtt/tests/test_mosquitto.py
@@ -2,7 +2,7 @@
 
 from testcontainers.mqtt import MosquittoContainer
 
-VERSIONS = ["1.6.15", "2.0.18"]
+VERSIONS = ["1.6.15", "2.0.18", "2.1.2"]
 
 
 @pytest.mark.parametrize("version", VERSIONS)