From nobody Tue May 30 09:18:13 2023 X-Original-To: questions@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QVmz06GYvz4Y8cb for ; Tue, 30 May 2023 09:18:20 +0000 (UTC) (envelope-from sysadmin.lists@mailfence.com) Received: from wilbur.contactoffice.com (wilbur.contactoffice.com [212.3.242.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4QVmyz63S9z3q3x for ; Tue, 30 May 2023 09:18:19 +0000 (UTC) (envelope-from sysadmin.lists@mailfence.com) Authentication-Results: mx1.freebsd.org; dkim=fail ("body hash did not verify") header.d=mailfence.com header.s=20210208-e7xh header.b=o1k5zFzT; spf=pass (mx1.freebsd.org: domain of sysadmin.lists@mailfence.com designates 212.3.242.68 as permitted sender) smtp.mailfrom=sysadmin.lists@mailfence.com; dmarc=pass (policy=quarantine) header.from=mailfence.com Received: from ichabod.co-bxl (ichabod.co-bxl [10.2.0.36]) by wilbur.contactoffice.com (Postfix) with ESMTP id C1A27101D for ; Tue, 30 May 2023 11:18:16 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1685438296; s=20210208-e7xh; d=mailfence.com; i=sysadmin.lists@mailfence.com; h=Date:From:To:Message-ID:In-Reply-To:References:Subject:MIME-Version:Content-Type:Content-Transfer-Encoding; l=2260; bh=81m7A6Cdz4Wew8vZuDRIqXHI8xS6/6YF73cJBIfyvt0=; b=o1k5zFzTgfVJMRk6ntX+OGmsumGO7yV8tuT92uz3d6wMCoqvEPqMZ9AtJiRKqNEH GGeaxP5zD6tYrP5A9FOXGsxaOZFwBoEtUn2g0GpWb6TUGGj6On96mD1usKlc+jikwiG n2MfKU9212Grt+LZ8x1migj4e3ePc4m0xYKc0j5Y2lotMHHNvg3q8gqp8jnNbpySnDe SpBEWRuBoQ1RKwftYPvJk/jr22fQ5QmYd2whqywIlDbMNR7RFYZ+4ewrJd3mZELA9le /1YgtsE3zD+/jlkdXPeXvN/Dm9TnF25Ar25InYbFI0kW4JQO3RjYvJoRM/4XHPMV1cK GvSHTpBKhQ== Date: Tue, 30 May 2023 11:18:13 +0200 (CEST) From: Sysadmin Lists To: questions@freebsd.org Message-ID: <2025846914.656453.1685438293844@ichabod.co-bxl> In-Reply-To: <00671d49-83b1-26a0-4e28-47eb0d7cb95c@holgerdanske.com> References: <1957739901.520492.1685310340560@ichabod.co-bxl> <0d0186c5-9542-1af3-2ce3-e28480b4b6d7@holgerdanske.com> <1961596841.3509648.1685359514813@fidget.co-bxl> <00671d49-83b1-26a0-4e28-47eb0d7cb95c@holgerdanske.com> Subject: Re: read and write back full disk to trigger relocation List-Id: User questions List-Archive: https://lists.freebsd.org/archives/freebsd-questions List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Mailer: ContactOffice Mail X-ContactOffice-Account: com:312482426 X-Spamd-Result: default: False [-2.51 / 15.00]; NEURAL_HAM_MEDIUM(-0.98)[-0.976]; NEURAL_HAM_SHORT(-0.94)[-0.943]; DMARC_POLICY_ALLOW_WITH_FAILURES(-0.50)[]; NEURAL_SPAM_LONG(0.30)[0.300]; R_SPF_ALLOW(-0.20)[+ip4:212.3.242.64/26]; MIME_GOOD(-0.10)[text/plain]; RCVD_IN_DNSWL_LOW(-0.10)[212.3.242.68:from]; XM_UA_NO_VERSION(0.01)[]; RCVD_TLS_LAST(0.00)[]; MLMMJ_DEST(0.00)[questions@freebsd.org]; MIME_TRACE(0.00)[0:+]; FROM_EQ_ENVFROM(0.00)[]; ASN(0.00)[asn:10753, ipnet:212.3.242.64/26, country:US]; DKIM_TRACE(0.00)[mailfence.com:-]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; DMARC_POLICY_ALLOW(0.00)[mailfence.com,quarantine]; PREVIOUSLY_DELIVERED(0.00)[questions@freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; TO_DN_NONE(0.00)[]; R_DKIM_REJECT(0.00)[mailfence.com:s=20210208-e7xh]; ARC_NA(0.00)[] X-Rspamd-Queue-Id: 4QVmyz63S9z3q3x X-Spamd-Bar: -- X-ThisMailContainsUnwantedMimeParts: N > ---------------------------------------- > From: David Christensen > Date: May 29, 2023, 4:12:24 PM > To: > Subject: Re: read and write back full disk to trigger relocation > > > Your mail client and my mail client (Thunderbird) indent things > differently. I have reformatted the above per Thunderbird conventions. > I have had to do this every time I reply to your messages. I do not > have this issue with most other messages I reply to. That doesn't surprise me. My mail client is web-based, but this provider seems hellbent on ruining what used to be a good service. Can't say I recommend them. > Testing dd(1) and gmirror(8): > > 2023-05-29 15:21:32 toor@vf1 ~ > # freebsd-version ; uname -a > 12.4-RELEASE-p2 > FreeBSD vf1.tracy.holgerdanske.com 12.4-RELEASE-p1 FreeBSD > 12.4-RELEASE-p1 GENERIC amd64 > > 2023-05-29 15:23:05 toor@vf1 ~ > # gmirror label mymirror ada3 ada4 > > 2023-05-29 15:24:11 toor@vf1 ~ > # gmirror status mymirror > Name Status Components > mirror/mymirror COMPLETE ada3 (ACTIVE) > ada4 (ACTIVE) > > 2023-05-29 15:52:41 toor@vf1 ~ > # dd if=/dev/ada3 of=/dev/ada3 bs=1m > dd: /dev/ada3: Operation not permitted > > 2023-05-29 15:53:45 toor@vf1 ~ > # dd if=/dev/ada4 of=/dev/ada4 bs=1m > dd: /dev/ada4: Operation not permitted > > 2023-05-29 15:53:52 toor@vf1 ~ > # dd if=/dev/mirror/mymirror of=/dev/mirror/mymirror bs=1m > 1023+1 records in > 1023+1 records out > 1073741312 bytes transferred in 3.299006 secs (325474224 bytes/sec) > > > This confirms that the kernel will not allow writes to mirror components > when they are active, as it should. If a process could write to a > component of a mirror, that would bypass the mirror driver, defeat the > purpose of the mirror, allow race conditions, and result in data loss/ > data corruption. > > > David > > That makes sense. I wouldn't recommend running it on a live system anyway. Probably wiser to boot into a livecd and run it on a single disk. gmirror shouldn't notice a difference since the data isn't presently corrupted, just decaying (is my guess). 3TB is a lot of data to process. -- Sent with https://mailfence.com Secure and private email