From owner-freebsd-stable@FreeBSD.ORG Fri Jan 22 21:31:52 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EEF771065676 for ; Fri, 22 Jan 2010 21:31:52 +0000 (UTC) (envelope-from mloftis@wgops.com) Received: from juggler.wgops.com (juggler.wgops.com [204.11.247.41]) by mx1.freebsd.org (Postfix) with ESMTP id C6AF58FC08 for ; Fri, 22 Jan 2010 21:31:52 +0000 (UTC) Received: by juggler.wgops.com (Postfix, from userid 65534) id 081DDA8110; Fri, 22 Jan 2010 14:31:51 -0700 (MST) X-Spam-ASN: X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on juggler.wgops.com X-Spam-Level: X-Spam-Status: No, score=-1.4 required=5.0 tests=ALL_TRUSTED autolearn=failed version=3.2.5 Received: from [192.168.1.44] (host-72-174-39-176.msl-mt.client.bresnan.net [72.174.39.176]) by juggler.wgops.com (Postfix) with ESMTPSA id DE337A810E for ; Fri, 22 Jan 2010 14:31:49 -0700 (MST) Date: Fri, 22 Jan 2010 14:31:55 -0700 From: Michael Loftis To: freebsd-stable@freebsd.org Message-ID: <7A1BFA601D973DD9D73B2952@[192.168.1.44]> In-Reply-To: <20100122210549.GA5038@mid.pc5.i.0x5.de> References: <717f7a3e1001120714m37aada69gfaa35f0f9b17f435@mail.gmail.com> <44678539@bb.ipt.ru> <717f7a3e1001142234y1de7ae15x6853e3ddcab4add9@mail.gmail.com> <717f7a3e1001192246o4dce4a82q57c05ff3f41b5feb@mail.gmail.com> <20100120074611.GA405@icarus.home.lan> <20100122210549.GA5038@mid.pc5.i.0x5.de> X-Mailer: Mulberry/4.0.8 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Virus-Scanned: clamav-milter 0.95.3 at juggler X-Virus-Status: Clean Subject: Re: Multiple serial consoles via null modem cable X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Jan 2010 21:31:53 -0000 --On Friday, January 22, 2010 10:05 PM +0100 Nicolas Rachinsky wrote: > * Jeremy Chadwick [2010-01-19 23:46 -0800]: >> You cannot do something like where box1 COM1 is wired to box2 COM1, and >> depending on what box you're on doing the "cu -l ttyu0" from, get a >> login prompt on the other. It doesn't work like that. :-) > > Isn't the reason for different dial-in and dial-out devices that this > should work? Or does that only work with modem? You can't with two directly connected machines. When the two are physically wired together, and getty is configured (via ttys) to fire up on the port it takes over the port. If you connect two machines via a null modem cable, both with getty on the same port, the getty's will be chatting with each other. The locking mechanism will "break" the chat loop when you try to use the dialout device on one end or the other but you may have to wait some time before the other end restarts getty (because it previously would have been dieing very rapidly due to login failures) A NULL modem connection is ALWAYS active. A regular modem, is NOT. It has a state of 'inactive' or 'waiting for ring' if you will. The correct way to do what you want is as others have suggested, two serial null modem cables, and two com ports on each machine.