From owner-freebsd-net@FreeBSD.ORG Thu Feb 10 20:28:15 2011 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 475081065670 for ; Thu, 10 Feb 2011 20:28:15 +0000 (UTC) (envelope-from pluknet@gmail.com) Received: from mail-qw0-f54.google.com (mail-qw0-f54.google.com [209.85.216.54]) by mx1.freebsd.org (Postfix) with ESMTP id ED8948FC0C for ; Thu, 10 Feb 2011 20:28:14 +0000 (UTC) Received: by qwj9 with SMTP id 9so1024144qwj.13 for ; Thu, 10 Feb 2011 12:28:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=KjVpCLAqdMu/mR5uX6R/oBamsLwACYj4rZID9jCiV4w=; b=GumnATnVnvEYJm64+P+RFcuiq2Um6TTZxoqu8rymtnpZjH1b65V4E+Cs3MEl3Q4mFK QtplXN7ZBOrJEcMP70zMNA6Nh4s60VyP8Isai/1D5iaIz09cMd0UpWC7X4kslwWQqM00 MCj40JZk/evX7xZHE3fhtIIJAIV8H9YEabwqU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=n/OOUOvP+EIWqCzC/dkWT7rzX5I45E4SdvzVRyAspYzL6hey8kFLiQGBVhQZ74tzDo ybsny1Dsp08XT38etjKqjR88BngUhO/lsYwYyPVxJzNRll1+6CSVT4DbaU++GX8lbs22 SU33rA3ZdTIl65rxjSFmkWGXtWC83dFeQ//L0= MIME-Version: 1.0 Received: by 10.229.231.21 with SMTP id jo21mr16648831qcb.119.1297369694032; Thu, 10 Feb 2011 12:28:14 -0800 (PST) Received: by 10.229.102.87 with HTTP; Thu, 10 Feb 2011 12:28:13 -0800 (PST) In-Reply-To: <19796.13124.805432.342309@oz.mt.att.com> References: <19796.13124.805432.342309@oz.mt.att.com> Date: Thu, 10 Feb 2011 23:28:13 +0300 Message-ID: From: Sergey Kandaurov To: Jay Borkenhagen Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: freebsd-net@freebsd.org Subject: Re: cannot set mtu > 1500 on em0 optical Gig-E X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Feb 2011 20:28:15 -0000 On 10 February 2011 21:49, Jay Borkenhagen wrote: > Hi, > > For quite a while now it appears that mtu on my gigabit ethernet fiber > em0 cards cannot be configured higher than the default 1500 bytes. > > Here's what I get when I attempt to set it lower and higher on a brand > new 8.2-RC3 box: > > =3D=3D=3D > sandbox# uname -v > FreeBSD 8.2-RC3 #0: Sun Jan 30 06:52:51 UTC 2011 =A0 =A0 root@almeida.cse= .buffalo.edu:/usr/obj/usr/src/sys/GENERIC > sandbox# > > sandbox# ifconfig em0 > em0: flags=3D8843 metric 0 mtu 15= 00 > =A0 =A0 options=3D18 > =A0 =A0 ether 00:d0:b7:7c:f8:01 > =A0 =A0 inet 10.1.2.3 netmask 0xffffff00 broadcast 10.1.2.255 > =A0 =A0 media: Ethernet autoselect > =A0 =A0 status: no carrier > sandbox# ifconfig em0 mtu 1499 > sandbox# ifconfig em0 | grep mtu > em0: flags=3D8843 metric 0 mtu 14= 99 > sandbox# ifconfig em0 mtu 1501 > ifconfig: ioctl (set mtu): Invalid argument > sandbox# ifconfig em0 | grep mtu > em0: flags=3D8843 metric 0 mtu 14= 99 > sandbox# ifconfig em0 mtu 1500 > sandbox# ifconfig em0 | grep mtu > em0: flags=3D8843 metric 0 mtu 15= 00 > sandbox# > > sandbox# pciconf -lv | sed -n '/em0@/,/em1/p' > em0@pci0:0:2:0: =A0class=3D0x020000 card=3D0x10008086 chip=3D0x10008086 r= ev=3D0x03 hdr=3D0x00 > =A0 =A0vendor =A0 =A0 =3D 'Intel Corporation' > =A0 =A0device =A0 =A0 =3D '82542 Gigabit Ethernet Controller' > =A0 =A0class =A0 =A0 =A0=3D network > =A0 =A0subclass =A0 =3D ethernet > em1@pci0:0:4:0: =A0class=3D0x020000 card=3D0x10008086 chip=3D0x10008086 r= ev=3D0x03 hdr=3D0x00 > sandbox# > > =3D=3D=3D > > However, back in the 6.2 days it allowed it: > > =3D=3D=3D > > [jayb@cactus ~]$ uname -v > FreeBSD 6.2-PRERELEASE #0: Tue Dec 26 16:53:18 EST 2006 =A0 =A0 root@cact= us.iplabs.att.com:/usr/obj/usr/src/sys/CACTUS > [jayb@cactus ~]$ > > [jayb@cactus ~]$ ifconfig em0 > em0: flags=3D8843 mtu 1500 > =A0 =A0 options=3D8 > =A0 =A0 inet 10.0.1.152 netmask 0xfffffffc broadcast 10.0.1.155 > =A0 =A0 ether 00:90:27:e3:0a:67 > =A0 =A0 media: Ethernet autoselect > =A0 =A0 status: no carrier > [jayb@cactus ~]$ > > [jayb@cactus ~]$ sudo ifconfig em0 mtu 9000 > [jayb@cactus ~]$ ifconfig em0 | grep mtu > em0: flags=3D8843 mtu 9000 > [jayb@cactus ~]$ > > [jayb@cactus ~]$ pciconf -lv | sed -n '/em0@/,/none0@/p' > em0@pci0:2:0: =A0 =A0class=3D0x020000 card=3D0x10008086 chip=3D0x10008086= rev=3D0x02 hdr=3D0x00 > =A0 =A0vendor =A0 =3D 'Intel Corporation' > =A0 =A0device =A0 =3D '82542 Gigabit Ethernet Controller' > =A0 =A0class =A0 =A0=3D network > =A0 =A0subclass =3D ethernet > none0@pci0:4:0: class=3D0x088000 card=3D0x0767101e chip=3D0x9063101e rev= =3D0x04 hdr=3D0x00 > [jayb@cactus ~]$ > Hmm.. Did jumbo frames really work on these cards for you? Intel claims: "Adapters based on the Intel=AE 82542 and 82573V/E controller do not support Jumbo Frames. These correspond to the following product names: * Intel=AE PRO/1000 Gigabit Server Adapter * Intel=AE PRO/1000 PM Network Connection " As seen from code, the behavior was changed to match the description ("keep old 82542 from using jumbo frames") and merged to 6-STABLE before 6.3. --=20 wbr, pluknet