Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755468AbZCEWPt (ORCPT ); Thu, 5 Mar 2009 17:15:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753414AbZCEWPk (ORCPT ); Thu, 5 Mar 2009 17:15:40 -0500 Received: from mx1.aecom.yu.edu ([129.98.1.51]:49288 "EHLO mx1.aecom.yu.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753209AbZCEWPk (ORCPT ); Thu, 5 Mar 2009 17:15:40 -0500 X-AuditID: 816201a0-a5e9dbb000001567-dd-49b04f0ab486 Mime-Version: 1.0 Message-Id: Date: Thu, 5 Mar 2009 17:14:47 -0500 To: linux-kernel@vger.kernel.org From: Maurice Volaski Subject: e1000 is subtly incompatible with jumbo frames Cc: jesse.brandeburg@intel.com, jeffrey.t.kirsher@intel.com Content-Type: text/plain; charset="us-ascii" ; format="flowed" X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 926 Lines: 18 I have a system using the e1000 driver with the MTU set to 9000. If I try FTP to get a file, the transfer does not start. Something about the 9000 MTU is preventing the NIC from receiving packets back from the FTP server. (The FTP server is on the same subnet and its NIC also has MTU 9000.) The 9000 MTU NIC works fine in every other respect, even allowing me to access the system via ssh. When I change the MTU to 1500, then FTP works fine. The problem is common to numerous kernel versions including 2.6.24 through 2.6.29-rc5. -- Maurice Volaski, mvolaski@aecom.yu.edu Computing Support, Rose F. Kennedy Center Albert Einstein College of Medicine of Yeshiva University -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/