diff --git a/source/libs/function/src/udfd.c b/source/libs/function/src/udfd.c
index 3b827a2f99a446b11236f53acda1fb4da0592e88..c10895139bdb256193f7fdcb190ff0ee418eeab7 100644
--- a/source/libs/function/src/udfd.c
+++ b/source/libs/function/src/udfd.c
@@ -970,6 +970,7 @@ int32_t udfdConnectToMnode() {
   connReq.connType = CONN_TYPE__UDFD;
   tstrncpy(connReq.app, "udfd", sizeof(connReq.app));
   tstrncpy(connReq.user, TSDB_DEFAULT_USER, sizeof(connReq.user));
+  // just use default password. this password is not checked by mnode since connection is from udfd
   char pass[TSDB_PASSWORD_LEN + 1] = {0};
   taosEncryptPass_c((uint8_t *)(TSDB_DEFAULT_PASS), strlen(TSDB_DEFAULT_PASS), pass);
   tstrncpy(connReq.passwd, pass, sizeof(connReq.passwd));
diff --git a/tests/script/tsim/query/udf.sim b/tests/script/tsim/query/udf.sim
index 522d3e1b51a137931bd02391e07c015f8a1210bd..fbf9d50c2568bb571349ae1b5874fed7c217f0e1 100644
--- a/tests/script/tsim/query/udf.sim
+++ b/tests/script/tsim/query/udf.sim
@@ -8,10 +8,12 @@ system sh/deploy.sh -n dnode1 -i 1
 system sh/cfg.sh -n dnode1 -c udf -v 1
 system sh/exec.sh -n dnode1 -s start
 sql connect
+sql alter user root pass 'taosdata2'
+system sh/exec.sh -n dnode1 -s stop
+system sh/exec.sh -n dnode1 -s start
 
 print ======== step1 udf
 system sh/compile_udf.sh
-sql alter user root pass 'taosdata2'
 sql create database udf vgroups 3;
 sql use udf;
 sql select * from information_schema.ins_databases;