From owner-freebsd-current@FreeBSD.ORG Fri Oct 31 09:50:32 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id AA6F016A4CE for ; Fri, 31 Oct 2003 09:50:32 -0800 (PST) Received: from pit.databus.com (p70-227.acedsl.com [66.114.70.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1195443FDD for ; Fri, 31 Oct 2003 09:50:31 -0800 (PST) (envelope-from barney@pit.databus.com) Received: from pit.databus.com (localhost [127.0.0.1]) by pit.databus.com (8.12.9p2/8.12.9) with ESMTP id h9VHoUp4079820; Fri, 31 Oct 2003 12:50:30 -0500 (EST) (envelope-from barney@pit.databus.com) Received: (from barney@localhost) by pit.databus.com (8.12.9p2/8.12.9/Submit) id h9VHoUwI079819; Fri, 31 Oct 2003 12:50:30 -0500 (EST) (envelope-from barney) Date: Fri, 31 Oct 2003 12:50:30 -0500 From: Barney Wolff To: Terry Lambert Message-ID: <20031031175030.GB78910@pit.databus.com> References: <20031029183808.M99053@prg.traveller.cz> <3FA223AB.797B2528@mindspring.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3FA223AB.797B2528@mindspring.com> User-Agent: Mutt/1.4.1i X-Scanned-By: MIMEDefang 2.37 cc: Michal Mertl cc: current@freebsd.org Subject: Re: jumbograms (& em) & nfs a no go X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Oct 2003 17:50:32 -0000 On Fri, Oct 31, 2003 at 12:56:11AM -0800, Terry Lambert wrote: > Michal Mertl wrote: > > I then left one computer at 4.9 and upgraded the other to 5.0. When I > > mount a partition from 5.0 machine I found out, that copying reliably > > works only from 5.0 to 4.9. The other way around I see messages 'em0: > > discard oversize frame (ether type 800 flags 3 len 67582 > max 6014)' on > > 5.0 and the copying stalls. On 4.9 machine I later see 'nfs server > > 10.0.0.2:/usr: not responding'. The interface is stuck for some time - can > > be revived by changing mtu back to 1500 and down/up sequence. > > Implies the sending host is not honoring the MTU restriction when > deciding whether or not to frag packets. 67582 looks awfully bogus even as a pre-frag length. How could that come over the wire? -- Barney Wolff http://www.databus.com/bwresume.pdf I'm available by contract or FT, in the NYC metro area or via the 'Net.