From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: Raid5 drive fail during grow and no backup Date: Thu, 04 Dec 2014 14:29:03 -0500 Message-ID: <5480B5FF.5050407@ubuntu.com> References: <5455A35C.2060000@turmel.org> <5458FC2A.1050308@turmel.org> <545CEDFB.6060806@gautschi.net> <545D8FBA.9090701@turmel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <545D8FBA.9090701@turmel.org> Sender: linux-raid-owner@vger.kernel.org To: Phil Turmel , "P. Gautschi" Cc: Vince , linux-raid@vger.kernel.org List-Id: linux-raid.ids -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/7/2014 10:36 PM, Phil Turmel wrote: > However, if the device with the bad sector is trying to recover > longer than the linux low level driver's timeout, bad things^TM > happen. Specifically, the driver resets the SATA (or SCSI) > connection and attempts to reconnect. During this brief time, it > will not accept further I/O, so the write back of the reconstructed > data fails. Then the device has experienced a *write* error, so MD > fails the drive. This is the out-of-the-box behavior of > consumer-grade drives in raid arrays. What? During the recovery action ( reset and retry ), a write being issued to the drive should just sit in the request queue until after the drive finishes being reset; it should not just be failed outright. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (MingW32) iQEcBAEBAgAGBQJUgLX+AAoJENRVrw2cjl5RHb4H+wWzuTFekQMwIoX7Vov5QjLh XyEmgbwqgtdcnsbQqtnNiQK0k8KVxQDW3xzWkB30PkOjWMfldES3dRjFXuNbZ0r1 FnJeIYbChFBnfJLp/BqHHOnL5YHD81HvENJ4M/OW6t9SpSiFuOieFe7WTEwHoh5t t9v/J0+x84CQu1q/AF7FRMkLE1fYhZieAMLTyKhbo5TmMm5XSP8eXumMCz+PXmvV tVN6rYejSozl1wfwa0l4N9jwkyYWLgbzFRIR7PuQNacywFyLhg0WtIPnqjNV6YuL rAl5VBFbHEn6BwklgxDWkzSIuOIt2ce6KIE0JZtqTGlDajhSUM+ojTPALLFcmLE= =4mKS -----END PGP SIGNATURE-----