From owner-freebsd-questions@freebsd.org Fri Nov 11 06:44:31 2016 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 98939C3BE0D for ; Fri, 11 Nov 2016 06:44:31 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mx01.qsc.de (mx01.qsc.de [213.148.129.14]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 614AE19E5 for ; Fri, 11 Nov 2016 06:44:31 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from r56.edvax.de (port-92-195-250-109.dynamic.qsc.de [92.195.250.109]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx01.qsc.de (Postfix) with ESMTPS id 5DBE13CF19; Fri, 11 Nov 2016 07:44:23 +0100 (CET) Received: from r56.edvax.de (localhost [127.0.0.1]) by r56.edvax.de (8.14.5/8.14.5) with SMTP id uAB6iMK9002718; Fri, 11 Nov 2016 07:44:22 +0100 (CET) (envelope-from freebsd@edvax.de) Date: Fri, 11 Nov 2016 07:44:22 +0100 From: Polytropon To: Mick mtn Cc: freebsd-questions@freebsd.org Subject: Re: Newbie Question: is there a rescue mode or shell access from loader? Message-Id: <20161111074422.7c3c82bb.freebsd@edvax.de> In-Reply-To: References: <20161111064322.541a76df.freebsd@edvax.de> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Nov 2016 06:44:31 -0000 Re-including mailing list, hope that's okay. On Thu, 10 Nov 2016 23:18:49 -0700, Mick mtn wrote: > Thank you, > I tried to interrupt the boot by repeatedly pressing the space bar as you > recommended however it had no effect. > The system continued the boot process and continued the loop > (boot,panic,reboot). > I can escape to the loader, it will allow me to give the unload command. > It will not however allow me to boot into single user mode. What happens when you issue the command "boot -s" at the loader prompt? You should end up in single user mode, / mounted r/o, no other partitions mounted, request for shell. > I inserted the FreeBSD 11 R amd64 dvd that I used to initially install the > system. It will now not recognize the dvd. > after holding the C on boot I do get a screen : > 1. > 2. > select CD-ROM Boot Type : > > no keystroke seems to be seen by the system. That doesn't look like typical FreeBSD behaviour. Sadly, using Macbooks is in my case restricted to using Mac OS X, so I have absolutely no experience booting them from "foreign" media or installing FreeBSD on them... :-( > I'm wondering if I may have a hardware failure of some sort. > But the system was running prior to my last batch of print set-up edits per > the Handbook section on printing. > along with the inclusion of visa_load="yes" into boot/loader.conf. Shouldn't that be vesa_load="YES"? > While in loader prompt it does not find > I've issued 'boot cdrom' and it reports "can't find kernel" > Im perplexed. What you see is fully correct. The loader does not have a "mount" internal command. It's fairly restricted - because interactive mounting is not part of what the loader does. In order to boot from CD-ROM, you need to act at an earlier stage, the "initial boot" program with the "boot:" prompt, where you can set the boot device. If you have passed that stage, you get the "Ok" prompt, the loader. Here you can use "unload" for kernels and kernel modules, "boot -s" to continue booting into single user mode, "boot -C" to boot from CD-ROM, as well as rudimentary "ls" and "more" internal commands. See table 12.1 here: https://www.freebsd.org/doc/handbook/boot-introduction.html Detailed information can be found in "man 8 boot": https://www.freebsd.org/cgi/man.cgi?query=boot&sektion=8&manpath=freebsd-release-ports -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...