diff --git a/src/gb/gprs_ns_vty.c b/src/gb/gprs_ns_vty.c
index 5a951dc..ee305ba 100644
--- a/src/gb/gprs_ns_vty.c
+++ b/src/gb/gprs_ns_vty.c
@@ -573,8 +573,16 @@
 
 int gprs_ns_vty_init(struct gprs_ns_inst *nsi)
 {
+	static bool vty_elements_installed = false;
+
 	vty_nsi = nsi;
 
+	/* Regression test code may call this function repeatedly, so make sure
+	 * that VTY elements are not duplicated, which would assert. */
+	if (vty_elements_installed)
+		return 0;
+	vty_elements_installed = true;
+
 	install_element_ve(&show_ns_cmd);
 	install_element_ve(&show_ns_stats_cmd);
 	install_element_ve(&show_nse_cmd);