Right now, we have code in update_router_descriptor_downloads() to launch a fetch for authority.z if we want to learn our IP from a directory fetch. We do this if: * We're a server * We don't have the Address option set * At least 20 minutes have passed since we last launched a router descriptor download * At least 20 minutes have passed since we last launched a Per discussion in bug legacy/trac#652, we could be even more quiet about launching these fetches. We could also require that * At least 20 minutes have passed since we last launched *any* appropriate directory op. * At least 20 minutes have passed since we got a new incoming connection on what we think our IP is. * At least 20 minutes have passed since we got confirmation of our current IP in a NETINFO cell We could also make the "20 minutes" value configurable by a networkstatus parameter. This is a minor issue, since the current behavior is inelegant, but not actually hurting anything.