diff --git a/ansible/roles/postgresql/defaults/main.json b/ansible/roles/postgresql/defaults/main.json
index abd9af3..ff00ca2 100644
--- a/ansible/roles/postgresql/defaults/main.json
+++ b/ansible/roles/postgresql/defaults/main.json
@@ -1,5 +1,5 @@
 {
 	"var_postgresql_listen_address": "localhost",
-	"var_postgresql_port": "5432"
+	"var_postgresql_port": 5432
 }
 
diff --git a/ansible/roles/postgresql/templates/postgresql.conf.j2 b/ansible/roles/postgresql/templates/postgresql.conf.j2
index 1b5c664..3b2847f 100644
--- a/ansible/roles/postgresql/templates/postgresql.conf.j2
+++ b/ansible/roles/postgresql/templates/postgresql.conf.j2
@@ -61,7 +61,7 @@ listen_addresses = '{{var_postgresql_listen_address}}'		# what IP address(es) to
 					# comma-separated list of addresses;
 					# defaults to 'localhost'; use '*' for all
 					# (change requires restart)
-port = {{var_postgresql_port}}				# (change requires restart)
+port = {{var_postgresql_port | string}}				# (change requires restart)
 max_connections = 100			# (change requires restart)
 #superuser_reserved_connections = 3	# (change requires restart)
 unix_socket_directories = '/var/run/postgresql'	# comma-separated list of directories
diff --git a/ansible/roles/postgresql/vardef.json b/ansible/roles/postgresql/vardef.json
new file mode 100644
index 0000000..0fc124f
--- /dev/null
+++ b/ansible/roles/postgresql/vardef.json
@@ -0,0 +1,15 @@
+{
+	"listen_address": {
+		"mandatory": false,
+		"type": "string"
+	},
+	"port": {
+		"mandatory": false,
+		"type": "integer"
+	},
+	"allow_md5_auth": {
+		"mandatory": false,
+		"type": "boolean"
+	}
+}
+