diff --git a/sandbox/hazelcast_dmz-dmz.xml b/sandbox/hazelcast_dmz-dmz.xml
index f1d3ecd02a5..160d06581f8 100644
--- a/sandbox/hazelcast_dmz-dmz.xml
+++ b/sandbox/hazelcast_dmz-dmz.xml
@@ -14,6 +14,7 @@
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <properties>
    <property name="hazelcast.discovery.enabled">true</property>
+	 <property name="hazelcast.logging.type">slf4j</property>
  </properties>
 <group>
 		<name>k8s</name>
diff --git a/sandbox/hazelcast_mz-mz.xml b/sandbox/hazelcast_mz-mz.xml
index f1d3ecd02a5..040c52de759 100644
--- a/sandbox/hazelcast_mz-mz.xml
+++ b/sandbox/hazelcast_mz-mz.xml
@@ -14,6 +14,7 @@
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <properties>
    <property name="hazelcast.discovery.enabled">true</property>
+   <property name="hazelcast.logging.type">slf4j</property>
  </properties>
 <group>
 		<name>k8s</name>