From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sridhar Samudrala Subject: Re: VLAN ID 0 with priority tagging Date: Thu, 06 Feb 2014 15:53:30 -0800 Message-ID: <52F4207A.6020408@gmail.com> References: <52E05901.6050601@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: "netdev@vger.kernel.org" Return-path: Received: from mail-oa0-f44.google.com ([209.85.219.44]:46440 "EHLO mail-oa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751004AbaBFXx0 (ORCPT ); Thu, 6 Feb 2014 18:53:26 -0500 Received: by mail-oa0-f44.google.com with SMTP id g12so3324973oah.31 for ; Thu, 06 Feb 2014 15:53:25 -0800 (PST) Received: from [192.168.1.4] (static-50-53-49-166.bvtn.or.frontiernet.net. [50.53.49.166]) by mx.google.com with ESMTPSA id b2sm15275043oed.7.2014.02.06.15.53.24 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 06 Feb 2014 15:53:25 -0800 (PST) In-Reply-To: <52E05901.6050601@us.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: On 1/22/2014 3:49 PM, Sridhar Samudrala wrote: > I am trying to send a packet with VLAN ID 0 and non-zero priority. > > The VLAN interfaces are created on 2 hosts using > ip link add link eth1 eth1.0 type vlan id 0 egress-qos-map 0:2 > > When i try to send a packet using ping/arping, on the sender side tcpdump > shows that the VLAN tag is added with ID 0 and priority 2. > > However, the receiver is receiving the packet with vlan tag stripped. > > I am seeing the same behavior with multiple NICs and also with a > switch in > between the 2 hosts or with the 2 hosts connected over loopback cable. > > It looks as if the driver on the send side is stripping the tag if > vlan id is 0. > Is this correct behavior or a bug? > Any clues on how to get priority tagging to work with vlan id 0? > I sent this note a few weeks back, but i haven't seen any response so far. Is priority tagging with VLAN ID 0 not supported or is this a bug? It looks like the NIC hardware is stripping the VLAN tag if the id is 0 even when VLAN tag is added by the software. Thanks Sridhar