diff --git a/fs_mgr/tools/dmctl.cpp b/fs_mgr/tools/dmctl.cpp
index 10efd0c..7273087 100644
--- a/fs_mgr/tools/dmctl.cpp
+++ b/fs_mgr/tools/dmctl.cpp
@@ -53,6 +53,7 @@
     std::cerr << "  getpath <dm-name>" << std::endl;
     std::cerr << "  getuuid <dm-name>" << std::endl;
     std::cerr << "  info <dm-name>" << std::endl;
+    std::cerr << "  replace <dm-name> <targets...>" << std::endl;
     std::cerr << "  status <dm-name>" << std::endl;
     std::cerr << "  resume <dm-name>" << std::endl;
     std::cerr << "  suspend <dm-name>" << std::endl;