From owner-freebsd-stable@FreeBSD.ORG Tue Sep 20 17:08:42 2011 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 5F8D6106564A; Tue, 20 Sep 2011 17:08:42 +0000 (UTC) (envelope-from olli@lurza.secnetix.de) Received: from lurza.secnetix.de (lurza.secnetix.de [IPv6:2a01:170:102f::2]) by mx1.freebsd.org (Postfix) with ESMTP id DA4968FC1D; Tue, 20 Sep 2011 17:08:41 +0000 (UTC) Received: from lurza.secnetix.de (localhost [127.0.0.1]) by lurza.secnetix.de (8.14.3/8.14.3) with ESMTP id p8KH8Pua094884; Tue, 20 Sep 2011 19:08:40 +0200 (CEST) (envelope-from oliver.fromme@secnetix.de) Received: (from olli@localhost) by lurza.secnetix.de (8.14.3/8.14.3/Submit) id p8KH8PKM094882; Tue, 20 Sep 2011 19:08:25 +0200 (CEST) (envelope-from olli) From: Oliver Fromme Message-Id: <201109201708.p8KH8PKM094882@lurza.secnetix.de> To: gpalmer@freebsd.org (Gary Palmer) Date: Tue, 20 Sep 2011 19:08:25 +0200 (CEST) In-Reply-To: <20110920141330.GE10165@in-addr.com> X-Mailer: ELM [version 2.5 PL8] MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.3.5 (lurza.secnetix.de [127.0.0.1]); Tue, 20 Sep 2011 19:08:40 +0200 (CEST) Cc: freebsd-stable@freebsd.org Subject: Re: 7-stable: Root mount problem (mpt, probing / timing related) 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: Tue, 20 Sep 2011 17:08:42 -0000 Gary Palmer wrote: > On Tue, Sep 20, 2011 at 03:41:58PM +0200, Oliver Fromme wrote: > > Hi, > > > > I've updated a server with mpt controller to the latest > > 7-stable (ok, it's 7-stable from last week). During the > > boot sequence, the disk connected to the mpt controller (da0) > > seems to be probed too late, i.e. just _after_ the kernel > > tries to mount the root file system. It's just a fraction > > of a second too late. > > > > This is a screen shot of the situation: > > > > http://www.secnetix.de/olli/tmp2/screenshot-boot.jpg > > > > Of course, I can enter "ufs:da0s1a" at the rootmount prompt, > > and the machine continues to boot fine. But this is a > > server that should be able to boot unattended, so I need > > this to be fixed. > > > > What's the "official" way to fix this? I think someone else > > had a similar problem some time ago, but a quick search of > > the lists doesn't yield anything. > > > > (BTW: Interestingly, the same machine boots fine without > > hickup when booting 8-stable which is installed on another > > Slice of the same disk. This could be just coincidence, > > maybe the timing of probing is slightly different between > > 7-stable and 8-stable.) > > Does increasing the > > kern.cam.scsi_delay > > loader tunable help at all? It seems to help ... I have now rebooted three times with scsi_delay set to 10000, and it worked so far (the problem did not always occur before, so I have to try several times). A value of 5000 was not sufficient. First I had tried kern.cam.boot_delay, which seems to be specifically for this kind of situation (according to the description), but it didn't help at all. Even very large values didn't help; I tried up to 30000. I'm a little surprised that scsi_delay helps, but boot_delay doesn't. I would have expected it to be the other way round. Anyway -- Thank you very much for the hint! Best regards Oliver -- Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M. Handelsregister: Registergericht Muenchen, HRA 74606, Geschäftsfuehrung: secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün- chen, HRB 125758, Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart FreeBSD-Dienstleistungen, -Produkte und mehr: http://www.secnetix.de/bsd "UNIX was not designed to stop you from doing stupid things, because that would also stop you from doing clever things." -- Doug Gwyn