From owner-freebsd-hackers@FreeBSD.ORG Tue Apr 29 12:02:10 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2295B1065674 for ; Tue, 29 Apr 2008 12:02:10 +0000 (UTC) (envelope-from jdc@parodius.com) Received: from mx01.sc1.parodius.com (mx01.sc1.parodius.com [72.20.106.3]) by mx1.freebsd.org (Postfix) with ESMTP id 109A38FC38 for ; Tue, 29 Apr 2008 12:02:09 +0000 (UTC) (envelope-from jdc@parodius.com) Received: by mx01.sc1.parodius.com (Postfix, from userid 1000) id A31431CC038; Tue, 29 Apr 2008 05:02:09 -0700 (PDT) Date: Tue, 29 Apr 2008 05:02:09 -0700 From: Jeremy Chadwick To: Sharad Chandra Message-ID: <20080429120209.GA44534@eos.sc1.parodius.com> References: <200804291613.14081.sharadc@in.niksun.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200804291613.14081.sharadc@in.niksun.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: FreeBSD Hackers Subject: Re: jumbo packets on em card. X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Apr 2008 12:02:10 -0000 On Tue, Apr 29, 2008 at 04:13:13PM +0530, Sharad Chandra wrote: > I am getting a problem in setting em card to 1000baseTX. It shows "active > status" with 100baseTX but as soon as i run "ifconfig em1 media 1000baseTX > mediaopt full-duplex", it says *no carrier*. how can i set it to 1000base? The PHYs support auto-negotiation of speed and duplex, as per the 802.3 standard. Do you have a gigabit switch? If so, does auto-negotiation (e.g. no "mediaopt" or "media" settings) work? If not, is the switch a managed switch? If so, try explicitly setting the port on the switch to 1000mbit, full duplex. If not, then consider buying another switch. Many consumer/residential switches do not do auto-negotiation properly, resulting in "no carrier" or worse (bad throughput). > And is it possible any how to send *jumbo packets* on this card or on bge card > (bge card is working with 1000base)? I tried nemesis tool, but i don't think > it can send bigger packets. BPF also seems to have limitaion upto 2K. man 4 em man 4 bge Keep in mind that if you use jumbo frames, your **entire network** needs to use jumbo frames. You cannot mix-and-match frame sizes. Chances are your ISPs or your co-lo provider doesn't support jumbo. -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |