From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Williams Subject: bridge interface initial carrier state Date: Mon, 11 Feb 2013 14:01:55 -0600 Message-ID: <1360612915.8633.6.camel@dcbw.foobar.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:38440 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759692Ab3BKUBz (ORCPT ); Mon, 11 Feb 2013 15:01:55 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r1BK1ta3010015 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 11 Feb 2013 15:01:55 -0500 Received: from [10.3.231.28] (vpn-231-28.phx2.redhat.com [10.3.231.28]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r1BK1tHG010979 for ; Mon, 11 Feb 2013 15:01:55 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Hi, I'm wondering if the initial carrier state of 'on' is intentional for a bridge without ports; immediately after adding ports, the carrier is recalculated and depends on the combined state of each port's carrier and STP forwarding state. So a userspace program attempting to decide whether the bridge was usable or not has to look at both (a) how many ports are available and (b) bridge carrier state, instead of just looking at the bridge carrier state. Dan