From owner-freebsd-questions@FreeBSD.ORG Tue Nov 25 18:13:19 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8A5CA1065676 for ; Tue, 25 Nov 2008 18:13:19 +0000 (UTC) (envelope-from frank@solensky.org) Received: from smtp02.lnh.mail.rcn.net (smtp02.lnh.mail.rcn.net [207.172.157.102]) by mx1.freebsd.org (Postfix) with ESMTP id 4E3D68FC1B for ; Tue, 25 Nov 2008 18:13:19 +0000 (UTC) (envelope-from frank@solensky.org) Received: from mr02.lnh.mail.rcn.net ([207.172.157.22]) by smtp02.lnh.mail.rcn.net with ESMTP; 25 Nov 2008 12:44:31 -0500 Received: from smtp01.lnh.mail.rcn.net (smtp01.lnh.mail.rcn.net [207.172.4.11]) by mr02.lnh.mail.rcn.net (MOS 3.8.6-GA) with ESMTP id PGS15678; Tue, 25 Nov 2008 12:44:18 -0500 (EST) Received: from unknown (HELO [10.0.1.200]) ([209.6.23.238]) by smtp01.lnh.mail.rcn.net with ESMTP; 25 Nov 2008 12:44:15 -0500 From: Frank Solensky To: freebsd-questions Content-Type: text/plain Date: Tue, 25 Nov 2008 12:44:14 -0500 Message-Id: <1227635054.6253.16.camel@frank-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit X-Junkmail-Status: score=10/50, host=mr02.lnh.mail.rcn.net X-Junkmail-SD-Raw: score=unknown, refid=str=0001.0A090206.492C3973.01F1,ss=1,fgs=0, ip=207.172.4.11, so=2007-10-30 19:00:17, dmn=5.7.1/2008-09-02 X-Junkmail-IWF: false Subject: Kernel crash before dumpon X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Nov 2008 18:13:19 -0000 I'm trying to get a dump off a machine with a 7.1-beta2 kernel that's been crashing during the boot process, following the instructions on http://www.freebsd.org/doc/en/books/developers-handbook/kerneldebug.html#KERNELDEBUG-OBTAIN I've recompiled the kernel with "-g" but no vmcore file appears so I'm assuming that the crash occurs before dumpon is executed. The page includes the following suggestion on how I might be able to proceed: Alternatively, the dump device can be hard-coded via the dump clause in the config(5) line of a kernel configuration file. This approach is deprecated and should be used only if a kernel is crashing before dumpon(8) can be executed. I tried adding config dump "/dev/ad4s3b" to the configuration file but that option appears to be no longer supported: the config command gives an error message of: root/dump/swap specification obsolete Is the paragraph above obsolete? If so, what's the preferred way to collect the dump? Thanks