diff --git a/lib/nodes/influxdb.c b/lib/nodes/influxdb.c
index 5b4b77594..bc98c2dfb 100644
--- a/lib/nodes/influxdb.c
+++ b/lib/nodes/influxdb.c
@@ -43,7 +43,7 @@ int influxdb_parse(struct node *n, json_t *json)
 	char *tmp, *host, *port, *lasts;
 	const char *server, *key;
 
-	ret = json_unpack_ex(json, &err, 0, "{ s: s, s: s, s?: o }",
+	ret = json_unpack_ex(json, &err, 0, "{ s: s, s: s }",
 		"server", &server,
 		"key", &key
 	);