=== src/or/routerlist.c
==================================================================
--- src/or/routerlist.c	(revision 15283)
+++ src/or/routerlist.c	(local)
@@ -4013,17 +4013,34 @@
   smartlist_free(no_longer_old);
 }
 
+/** How often should we launch a server/authority request to be sure of getting
+ * a guess for our IP? */
+/*XXXX021 this info should come from netinfo cells or something, or we should
+ * do this only when we aren't seeing incoming data. see bug 652. */
+#define DUMMY_DOWNLOAD_INTERVAL (20*60)
+
 /** Launch downloads for router status as needed. */
 void
 update_router_descriptor_downloads(time_t now)
 {
   or_options_t *options = get_options();
+  static time_t last_dummy_download = 0;
   if (should_delay_dir_fetches(options))
     return;
   if (directory_fetches_dir_info_early(options)) {
     update_router_descriptor_cache_downloads_v2(now);
   }
   update_consensus_router_descriptor_downloads(now);
+
+  if (server_mode(options) &&
+      last_routerdesc_download_attempted + DUMMY_DOWNLOAD_INTERVAL < now &&
+      last_dummy_download + DUMMY_DOWNLOAD_INTERVAL < now) {
+    /* If we haven't tried to get any routerdescs in a long time, try a dummy
+       fetch now. */
+    last_dummy_download = now;
+    directory_get_from_dirserver(DIR_PURPOSE_FETCH_SERVERDESC,
+                                 ROUTER_PURPOSE_GENERAL, "authority.z", 1);
+  }
 }
 
 /** Launch extrainfo downloads as needed. */