From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: Reshape stalled at first badblock location (was: RAID 5 --assemble doesn't recognize all overlays as component devices) Date: Wed, 22 Feb 2017 11:17:37 -0500 Message-ID: References: <20170221175801.wt64t2tzcvg3sfmc@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: George Rapp , Shaohua Li Cc: Linux-RAID , Matthew Krumwiede , NeilBrown , Jes.Sorensen@gmail.com List-Id: linux-raid.ids On 02/21/2017 08:12 PM, George Rapp wrote: > Before I proceed for real, does clearing the badblocks log and > assembling the array seem like my best option? Yes. And consider disabling badblocks on all of your arrays. The badblocks feature does nothing but guarantee that errors encountered on a device become uncorrectable, even if the cause of the error was a transient communications or power problem, not a true media flaw. Bad block tracking at the OS level is appropriate for ancient MFM and RLL devices that lack modern firmware, or similar low-level devices. And since the MD raid bad block tracking feature does *not* provide redirects to usable spare sectors, the feature is useless for such devices, too. MD raid currently does *nothing* when a badblock entry reduces the redundancy available for a particular sector in an array. The badblocks feature is incomplete, has no upside for modern component devices, and should not be used. Phil