From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Fjellstrom Subject: Re: Riad scrub generated errors, should I worry? Date: Mon, 02 Mar 2015 10:43:34 -0700 Message-ID: <1786620.4mivBfObx3@balsa> References: Reply-To: thomas@fjellstrom.ca Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Mikael Abrahamsson Cc: "Wilson, Jonathan" , linux-raid@vger.kernel.org List-Id: linux-raid.ids On Mon 02 Mar 2015 04:22:00 PM Mikael Abrahamsson wrote: > On Mon, 2 Mar 2015, Wilson, Jonathan wrote: > > While the monthly scrub was running the following errors (at the bottom > > of the post, copied from syslog) were issued. > > As soon as you get UNC, it's the drive reporting that it can't > successfully read a sector. Usually this sector is then reported as > "pending" in your SMART output. > > Since the log you provided shows a lot of sectors being corrected and you > after that have 0 pending sectors on the drive, I'd say you are now fine. > I would run a new scrub manually in a few days just to check, but you > might be fine going forward. There is no really good way to know, but > generally, a drive that throws a bunch of UNC should be monitored so this > isn't becoming a common problem. I tend to replace drives that have thrown > these kinds of errors if it happens on any kind of regular basis. Dumb question, but after pending, I assume they go into the reallocated column? I think after a certain number of those, you should start thinking about a replacement. Like with my recent issues, I had two drives with a few too many reallocated sectors. One was over 16k and the other was over 32k. They still "work", but I replaced them with WD Reds anyhow. Another drive seemed to max out the start-stop count field at 65536. Hah. No more cheap desktop seagates in raid for this fellow. -- Thomas Fjellstrom thomas@fjellstrom.ca