From owner-freebsd-stable@FreeBSD.ORG Mon Mar 16 16:10:40 2015 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 74A69F5F; Mon, 16 Mar 2015 16:10:40 +0000 (UTC) Received: from mx2.paymentallianceintl.com (mx2.paymentallianceintl.com [216.26.158.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mx2.paymentallianceintl.com", Issuer "Go Daddy Secure Certification Authority" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 30A38AD4; Mon, 16 Mar 2015 16:10:39 +0000 (UTC) Received: from firewall.mikej.com (162-230-214-65.lightspeed.lsvlky.sbcglobal.net [162.230.214.65]) by mx2.paymentallianceintl.com (8.15.1/8.15.1) with ESMTPS id t2GFsr2f014147 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 16 Mar 2015 11:54:54 -0400 (EDT) (envelope-from mikej@mikej.com) X-Authentication-Warning: mx2.paymentallianceintl.com: Host 162-230-214-65.lightspeed.lsvlky.sbcglobal.net [162.230.214.65] claimed to be firewall.mikej.com Received: from mail.mikej.com (firewall [192.168.6.63]) by firewall.mikej.com (8.15.1/8.14.9) with ESMTP id t2GFsqr8089598; Mon, 16 Mar 2015 11:54:52 -0400 (EDT) (envelope-from mikej@mikej.com) X-Authentication-Warning: firewall.mikej.com: Host firewall [192.168.6.63] claimed to be mail.mikej.com MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 16 Mar 2015 11:54:52 -0400 From: Michael Jung To: John Baldwin Subject: Re: savecore problem In-Reply-To: <2959054.c91S7azMUP@ralph.baldwin.cx> References: <2959054.c91S7azMUP@ralph.baldwin.cx> Message-ID: <2142548d6fac1894597a45a042966c7a@mail.mikej.com> X-Sender: mikej@mikej.com User-Agent: Roundcube Webmail/1.0.4 Cc: owner-freebsd-stable@freebsd.org, freebsd-stable@freebsd.org, Brandon Allbery , Michael BlackHeart X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Mar 2015 16:10:40 -0000 On 2015-03-16 11:23, John Baldwin wrote: > On Monday, March 16, 2015 10:17:54 AM Brandon Allbery wrote: >> On Mon, Mar 16, 2015 at 9:40 AM, Michael BlackHeart >> >> wrote: >> >> > Hello there. I've got a problem. Recently my personal server issued a >> > kernel panic. Then there's a dump and so on. But there's no dump >> > information after reboot. I do not know what was really the panic cause but >> > assume that savecore failed because of RAID. >> > >> > Problem - minidump was done (I saw it was) but was not recovered by >> > savecore after reboot into /var/vrash >> > >> (...) >> >> > /dev/ufs/varfs /var ufs rw,noatime >> > 2 2 >> > >> >> Last I checked, savecore had to happen very early --- before >> filesystems >> other than / are mounted. > > No, it can happen after that. What really has to happen is that you > don't > use swap (if you are dumping to your swap partition) before savecore > runs. Can someone elaborate on not using swap as a dump device a little more? I have had instances in the past were I had issues with getting a core dump and resorted to a dedicated dump device but didn't investigate further nor have I read this as a requirement. A second question - Can a USB devices be used reliably for a dump device for ZFS on boot systems? Regards, Michael Jung