+ node = vlib_get_node (vm, node_index);
+
+ if ((node->flags & VLIB_NODE_FLAG_TRACE_SUPPORTED) == 0)
+ {
+ error = clib_error_create ("node '%U' doesn't support per-node "
+ "tracing. There may be another way to "
+ "initiate trace on this node.",
+ format_vlib_node_name, vm, node_index);
+ goto done;
+ }
+
+ if (filter)
+ {
+ if (vlib_enable_disable_pkt_trace_filter (1 /* enable */ ))
+ {
+ error = clib_error_create ("No packet trace filter configured...");
+ goto done;
+ }
+ }
+