From owner-freebsd-hackers Mon Feb 25 11: 0:22 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from rwcrmhc54.attbi.com (rwcrmhc54.attbi.com [216.148.227.87]) by hub.freebsd.org (Postfix) with ESMTP id 518D037B405; Mon, 25 Feb 2002 11:00:15 -0800 (PST) Received: from InterJet.elischer.org ([12.232.206.8]) by rwcrmhc54.attbi.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP id <20020225190014.BTEF1214.rwcrmhc54.attbi.com@InterJet.elischer.org>; Mon, 25 Feb 2002 19:00:14 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id KAA89232; Mon, 25 Feb 2002 10:51:47 -0800 (PST) Date: Mon, 25 Feb 2002 10:51:46 -0800 (PST) From: Julian Elischer To: Bakul Shah Cc: Terry Lambert , Michael Smith , "George V. Neville-Neil" , freebsd-hackers@freebsd.org Subject: Re: Kernel Debugging over the Ethernet? In-Reply-To: <200202251821.NAA13901@marlborough.cnchost.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Mon, 25 Feb 2002, Bakul Shah wrote: > > The value of network debugging to me is not that I can > > avoid buying a serial cable (big deal), it's that I can > > do the debugging remotely. > > Agreed. > > > If I'm going to ssh into a local machine and debug from > > there, then I can use a serial cable. > > The serial cable solution does not scale too well when you > have many people simulteneously debugging multiple kernels. > If you use 8-port serial cards on a machine and connect every > other machine's serial console to it, that machine can become > the bottleneck + even in a lab keeping track of all the > serial cables etc. can be a pain. For us the ability to log > in any test machine and debug any other test machine was very > valuable. I hook my development machines up in pairs, with com1 and com2 cross connected. com1 -> com2 and visa versa. tip com2 on any machine gives me the serial console for it's partner. and gdb looks at com1, expecting to find the serial gdb output coming out of com2 on it's partner. Having said that.. network debugging is good, thuogh ai have a suspicion that the extent of the perturbations made into the system might lead to a larger class of "heisenbugs", for which a reversion to the serial cable or even ddb may be required. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message