--- a/sys/netgraph7/ng_sample.c
+++ b/sys/netgraph7/ng_sample.c
@@ -232,6 +232,7 @@
 	} else if (strcmp(name, NG_XXX_HOOK_DOWNSTREAM) == 0) {
 		/* Example of simple predefined hooks. */
 		/* do something specific to the downstream connection */
+		xxxp->downstream_hook.dlci = -1;
 		xxxp->downstream_hook.hook = hook;
 		NG_HOOK_SET_PRIVATE(hook, &xxxp->downstream_hook);
 	} else if (strcmp(name, NG_XXX_HOOK_DEBUG) == 0) {