From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Mamedov Subject: Re: SMART, RAID and real world experience of failures. Date: Fri, 6 Jan 2012 06:42:22 +0600 Message-ID: <20120106064222.38c0f1b5@natsu> References: <4F063808.6040000@crc.id.au> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/H_ixVYiYZZO1bipsyZWaLQt"; protocol="application/pgp-signature" Return-path: In-Reply-To: <4F063808.6040000@crc.id.au> Sender: linux-raid-owner@vger.kernel.org To: Steven Haigh Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/H_ixVYiYZZO1bipsyZWaLQt Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Fri, 06 Jan 2012 10:53:44 +1100 Steven Haigh wrote: > So, in the spirit of experimentation, I did the following: > # mdadm /dev/md2 --manage --fail /dev/sdd > # mdadm /dev/md2 --manage --remove /dev/sdd > # dd if=3D/dev/zero of=3D/dev/sdd bs=3D10M > # mdadm /dev/md2 --manage --add /dev/sdd Congratulations on doing absolutely the right thing, IMO :) > Has the sector with the read failure been remapped and hidden from view? More likely the drive decided the sector wasn't bad, after all. E.g. by ove= rwriting the sector and thus allowing the drive to throw away old user data= from it, you have also let the drive to rewrite the ECC or system area of = that sector, or whatever they have today in hard drives on the low level. If it was indeed remapped, then the logic would also require an increase in= Reallocated_Sector_Ct; but SMART attribute readings do have a lot of pecul= iarities, many of which are also vendor-specific. > Is it still (more?) likely to fail in the near future? In my experience not at all, unless you start getting stuff like this every= week. --=20 With respect, Roman ~~~~~~~~~~~~~~~~~~~~~~~~~~~ "Stallman had a printer, with code he could not see. So he began to tinker, and set the software free." --Sig_/H_ixVYiYZZO1bipsyZWaLQt Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEARECAAYFAk8GQ28ACgkQTLKSvz+PZwi/vwCfWQDSHpqkiw1aVzmkyN6XRmyT MMkAn29pPXZPgcMBVQD6JGYaYuj6OAaJ =Mro0 -----END PGP SIGNATURE----- --Sig_/H_ixVYiYZZO1bipsyZWaLQt--