From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8FF7ECAAA1 for ; Mon, 12 Sep 2022 09:26:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229953AbiILJ0h (ORCPT ); Mon, 12 Sep 2022 05:26:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229935AbiILJ0c (ORCPT ); Mon, 12 Sep 2022 05:26:32 -0400 Received: from rin.romanrm.net (rin.romanrm.net [IPv6:2001:bc8:2dd2:1000::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12A7825EAC for ; Mon, 12 Sep 2022 02:26:29 -0700 (PDT) Received: from nvm (nvm2.home.romanrm.net [IPv6:fd39::4a:3cff:fe57:d6b5]) by rin.romanrm.net (Postfix) with SMTP id 319AE5F9; Mon, 12 Sep 2022 09:26:26 +0000 (UTC) Date: Mon, 12 Sep 2022 14:26:24 +0500 From: Roman Mamedov To: Reindl Harald Cc: Wols Lists , Gandalf Corvotempesta , Linux RAID Mailing List Subject: Re: 3 way mirror Message-ID: <20220912142624.63ba4b5c@nvm> In-Reply-To: References: <53f5754d-e3e2-a8ba-bedb-07eb2b594595@thelounge.net> <2bcebfce-6def-38f8-99be-1f5702905f94@youngman.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On Mon, 12 Sep 2022 10:16:55 +0200 Reindl Harald wrote: > > That's called paranoia > > that's called common sense > > > ALL drives have hiccups when there's absolutely > > nothing wrong with them. What are the manufacturer's error figures? > > Expect at least one error every two or three complete passes of pretty > > much every large big disk nowadays? > i don't expect any SMART error at all and if one hits after years of > uptime fine that the drive don't fail completly - but would i trust it? no! I have multiple drives (Hitachi) which have developed around 3 to 10 reallocated sectors, and then just continue to work for years, not increasing those further. Throwing them away would be uneconomical. Not always a reallocated sector is a sign of impeding failure, what you need to look for is if there is more than one, and the count is increasing quickly. Generally though, if you are way too concerned about individual drive failures, it could be a sign that you do not have a robust enough backup scheme in place. -- With respect, Roman