From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Siebenmann Subject: Re: Bug? GRE tunnel periodically won't transmit some packets Date: Tue, 08 Nov 2011 02:08:19 -0500 Message-ID: <20111108070819.C643236221@apps0.cs.toronto.edu> References: <1320734606.8976.0.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Chris Siebenmann , netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from cliff.cs.toronto.edu ([128.100.3.120]:34470 "EHLO cliff.cs.toronto.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751314Ab1KHHIU (ORCPT ); Tue, 8 Nov 2011 02:08:20 -0500 In-reply-to: eric.dumazet's message of Tue, 08 Nov 2011 07:43:26 +0100. <1320734606.8976.0.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: | Le mardi 08 novembre 2011 =C3=A0 01:17 -0500, Chris Siebenmann a =C3=A9= crit : | > | Le lundi 07 novembre 2011 =C3=A0 11:21 -0500, Chris Siebenmann a = =C3=A9crit : | > | > I have a weird problem where a GRE tunnel periodically won't tr= ansmit | > | > some (TCP) packets, while at the same time it will transmit oth= ers just | > | > fine. This is happening in the current kernel.org git head kern= el as | > | > well as earlier ones. | > [...] | > | Do you have any errors on : | > |=20 | > | ip -s -d link show dev greXXXX | >=20 | > I do indeed. When the problem is happening, I see TX errors counti= ng | > up one-for-one with packets that are not transmitted (and no RX | > errors). Otherwise I don't see any errors. The other end of the GRE | > tunnel shows no errors (TX or RX). [..] | OK, but could you please report the exact "ip -s -d link gre..." | output ? Sure. Here it is: 7: extun: mtu 1200 qdisc noqueue state = UNKNOWN=20 link/gre 66.96.18.208 peer 128.100.3.58 gre remote 128.100.3.58 local 66.96.18.208 dev ppp0 ttl inherit=20 RX: bytes packets errors dropped overrun mcast =20 2793721 17015 0 0 0 0 =20 TX: bytes packets errors dropped carrier collsns=20 2242148 26824 18 0 0 0 =20 (The packet and byte counts were much lower when the problem happened; this time around it happened relatively soon after I rebooted my machin= e and brought up the PPPoE and GRE links, but hasn't happened since and I've been using the GRE link.) =46or vaguely historical reasons I don't use 'greXXX' as the name of the GRE tunnel. I have a 'gre0' device, but it is not up. In case it matters, its output is: 6: gre0: mtu 1476 qdisc noop state DOWN=20 link/gre 0.0.0.0 brd 0.0.0.0 gre remote any local any ttl inherit nopmtudisc=20 RX: bytes packets errors dropped overrun mcast =20 0 0 0 0 0 0 =20 TX: bytes packets errors dropped carrier collsns=20 0 0 0 0 0 0 =20 Let me know if you want a full dump of 'ip link show' (with or without verbosity). - cks