From owner-freebsd-net@FreeBSD.ORG Tue Oct 28 17:54:59 2008 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 D47171065672 for ; Tue, 28 Oct 2008 17:54:59 +0000 (UTC) (envelope-from ndenev@gmail.com) Received: from wx-out-0506.google.com (wx-out-0506.google.com [66.249.82.225]) by mx1.freebsd.org (Postfix) with ESMTP id 881978FC16 for ; Tue, 28 Oct 2008 17:54:59 +0000 (UTC) (envelope-from ndenev@gmail.com) Received: by wx-out-0506.google.com with SMTP id s17so882152wxc.7 for ; Tue, 28 Oct 2008 10:54:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=ZqOi9/Ej2xrgrIf6yxyzmzZjLFzLLwCuGB58rriFCuU=; b=s5Q7cV5NlczVukipqKHkXZzzOKagxBv5aOq2N/CeRiZnLn2kJGHtjnN97JM98R7Ig6 2qA0yVjsXzjbFPz7Sfa9DSTbl9IGxkbEtAVhZcevMYV/gjD3YSMg6rVSEU/aoBgvfrJY 3QJAFgTusSb78nkqmUxEfag+dZqZBLFzH+wf4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=WnqZAQlEieRTkdlHQPBk7uLLWc79RNQP4KnxmrFHN9Ee14DBq6AWd/eaykHOfGl2V9 Th1GSPoETXZWGCtsaYbZ1QvN07gYmJTl51qdsnpK+qZuaovnYJAIZPfAL0NTOmzfptGb k1hsn8RI3xMs59s0OVpx2RGVzlZwXMgMdFPQ4= Received: by 10.103.220.18 with SMTP id x18mr3551751muq.81.1225216497367; Tue, 28 Oct 2008 10:54:57 -0700 (PDT) Received: from MYTAHT.totalterror.net ([87.121.19.243]) by mx.google.com with ESMTPS id u26sm2339168mug.5.2008.10.28.10.54.54 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 28 Oct 2008 10:54:55 -0700 (PDT) Message-Id: <84671113-DA04-4EFA-8640-E9AD2F09BB34@gmail.com> From: Nikolay Denev To: Jack Vogel In-Reply-To: <2a41acea0810280941g6c9846y6e0d4b8b19313e0a@mail.gmail.com> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v929.2) Date: Tue, 28 Oct 2008 19:54:48 +0200 References: <2a41acea0810280941g6c9846y6e0d4b8b19313e0a@mail.gmail.com> X-Mailer: Apple Mail (2.929.2) Cc: freebsd-net@freebsd.org Subject: Re: ifconfig em0 mtu 9000 does not update the routing table 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: Tue, 28 Oct 2008 17:54:59 -0000 On 28 Oct, 2008, at 18:41 , Jack Vogel wrote: > It can't change the route table when you've given it no address: > > IE. ifconfig em0 HOSTNAME mtu 9000 will update it just fine. > > Cheers, > > Jack > > > On Tue, Oct 28, 2008 at 6:15 AM, Nikolay Denev > wrote: > Hello, > > As the subject says, I'm trying to enable jumbo frames on running > machine by setting > ifconfig em0 mtu 9000 by hand, but nothing changed, and I've fount > that when I list > the routing table with the MTU column it shows the connected routes > still with MTU 1500. > Is this supposed to work this way? I understand that making ifconfig > touch the routing table is ugly hack, but maybe the routing code can > be notified for interface changes by some other mechanism? > > btw, this is on 7-STABLE with if_em(4) interfaces. > > -- > Regards, > Nikolay Denev > Hi Jack, Yes, I understand that, It just looked logical to me to update the existing entries (directly attached) if no address is given, so one can use the mtu knob alone. Anyways, one rarely touches the mtu alone and this not a real problem, I've just tried to enable jumbo frames on two running machines with just the ifconfig em0 mtu 9000 line and wondered why it does not work for a minute. Thanks! -- Regards, Nikolay Denev