From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from frost.carfax.org.uk ([85.119.82.111]:43826 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751540AbbIOUiQ (ORCPT ); Tue, 15 Sep 2015 16:38:16 -0400 Date: Tue, 15 Sep 2015 20:38:15 +0000 From: Hugo Mills To: Timofey Titovets Cc: linux-btrfs Subject: Re: Csum I/O Error Message-ID: <20150915203815.GC28645@carfax.org.uk> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="w7PDEPdKQumQfZlR" In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: --w7PDEPdKQumQfZlR Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Sep 15, 2015 at 10:59:48PM +0300, Timofey Titovets wrote: > Hi list, > i've catch a io error, caused by csum mismatch > Can i force fs to read data? > This is really not a cool, if only way is use btrfs restore. > > #Info vm machin, after power failure get 2 blocks with errors, and one > mysql table, can't be readed by mysql (and also, i can't just dump it) The data is corrupt, or at the very least deeply untrustworthy. At this point, the easiest thing to do is use dd_rescue or ddrescue on it, which will skip the unreadable sectors and replace them with zeroes -- which is no worse than the random data you're likely to encounter from reading the broken data that the FS is (rightly) protecting you from. Hugo. -- Hugo Mills | A diverse working environment: Di longer you vork hugo@... carfax.org.uk | here, di verse it gets http://carfax.org.uk/ | PGP: E2AB1DE4 | --w7PDEPdKQumQfZlR Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJV+IG3AAoJEFheFHXiqx3kJwkP/jGOduIVn/4WVBlD8NQYBplP HWtR6QWI4qDzxpkcyb1goFK4YsKtR7PPJ8YRRFkjwdBNkh+cUfRlOn1HjxsYYN+X v/L/0AskwNTzm/jAo0jlfrmThzmKkmZxTjvqps0Z9ahVZPFW0aZXCUlBDjTAsXKU zWFJ+Wp4jXU+ctQt38P7QlUhdMDXJ1PIqbSgENIzkZ17mzwKaYsGlGlB8hBfsBuK j7Ylg06UNcxivXnYLJ9xp8p+NDP8VZpIzx+3o6GlucgAe8B5s9vjS9kbNOe6GBMX kURfc4NGyK1u8Xq2k8Z6PaUFmYkqQkMPAQh1vHOISooyhBpULVkr/41rQxIgy9qu DMRWwAUdzhaJ/uN/GICNHF6pdNYn9XdNkbQ6eJVfQHpMBxOLCOH1KjdZDUHCpXtt KiTWShfvHGqoABAXrOlsZ+J4dieyFSa4l8ZUQ+mMCv3YMlkm+23rwqGYxPXOA2JU jUUTJAlxqgF/wHG3r+b5imIDUxBB/ZjdL7MWpSkdbsRVLiRAzxvho6HFxIxcjlO+ QCBwyaX9jupk4n7dIjX7xdS7xbVFrvLF58l6gyluT40pm5jUxCcZPEuqfsTtNmWD PmSqRtL0KwOsefDXfchHgnN57FavvAnHaYCzYiQ7RDif/WqHygOdEkfxqVq9dMNj BKjE/Iii0OlhKnVqmcgR =WTjf -----END PGP SIGNATURE----- --w7PDEPdKQumQfZlR--