From owner-freebsd-virtualization@freebsd.org Sat Jan 9 17:29:56 2021 Return-Path: Delivered-To: freebsd-virtualization@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 786544DD5C3 for ; Sat, 9 Jan 2021 17:29:56 +0000 (UTC) (envelope-from freebsd-doc@fjl.co.uk) Received: from bs1.fjl.org.uk (bs1.fjl.org.uk [84.45.41.196]) by mx1.freebsd.org (Postfix) with ESMTP id 4DCn6C40G2z3lyP for ; Sat, 9 Jan 2021 17:29:54 +0000 (UTC) (envelope-from freebsd-doc@fjl.co.uk) Received: from [192.168.1.94] (host109-149-245-241.range109-149.btcentralplus.com [109.149.245.241]) (authenticated bits=0) by bs1.fjl.org.uk (8.14.4/8.14.4) with ESMTP id 109HTq9F010758 for ; Sat, 9 Jan 2021 17:29:52 GMT (envelope-from freebsd-doc@fjl.co.uk) Subject: Re: Zfs mount error on boot To: freebsd-virtualization@freebsd.org References: From: freebsd-doc@fjl.co.uk Message-ID: Date: Sat, 9 Jan 2021 17:30:45 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-GB X-Rspamd-Queue-Id: 4DCn6C40G2z3lyP X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of freebsd-doc@fjl.co.uk designates 84.45.41.196 as permitted sender) smtp.mailfrom=freebsd-doc@fjl.co.uk X-Spamd-Result: default: False [-0.51 / 15.00]; MID_RHS_MATCH_FROM(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; TO_MATCH_ENVRCPT_ALL(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:84.45.41.196]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-virtualization@freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-0.11)[-0.107]; DMARC_NA(0.00)[fjl.co.uk]; NEURAL_SPAM_SHORT(1.00)[1.000]; RCVD_IN_DNSWL_MED(-0.20)[84.45.41.196:from]; FROM_NO_DN(0.00)[]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:25577, ipnet:84.45.0.0/17, country:GB]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[freebsd-virtualization]; RECEIVED_SPAMHAUS_PBL(0.00)[109.149.245.241:received] X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 09 Jan 2021 17:29:56 -0000 On 09/01/2021 17:11, Brandon helsley wrote: > I am using VirtualBox 6.1 and have had another problem booting after an error with the system. I have made this post about the failure to boot before with screenshots on virtualbix forums but they told me it's an error with FreeBSD and to search for help there. Since I ran into the problem again I thought I would make this post. Also, this occurred after canceling an unsafe build of apache24 with Cntrl c and then rebooting. Below I have included a copy paste of part of the last log file where I think it displays what went wrong. > > ZFS: I/o error - all block copies unavailable > ZFS: can't read MOS of pool root > gotzfsboot: failed to mount default pool root > FreeBSD/x86 boot > ZFS: I/O error - blocks larger than 16777216 are not supported > ZFS: can't find dataset 0 > Default: root/<0x0>: > boot: _ > Well either FreeBSD has flipped, or there's something wrong with your ZFS data. (obvs.) What I do at times like this is mount he zpool on something else and find out which it is. If your datasets normally end up mounted on / (likely if you're booting off it), make sure you import using the option altroot=/something/other/than/root or you'll end up with no OS afterwards. readonly=off is also a good one. Good luck, and if you're not familiar with ZFS to import volumes, please ask. The above advice on altroot was a timely reminder, not a tutorial! Frank.