From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from slmp-550-94.slc.westdc.net ([50.115.112.57]:49594 "EHLO slmp-550-94.slc.westdc.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752090Ab3H0Djt (ORCPT ); Mon, 26 Aug 2013 23:39:49 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 6.5 \(1508\)) Subject: Re: Question: How can I recover this partition? (unable to find logical $hugenum len 4096) From: Chris Murphy In-Reply-To: <20130826193110.GO3115@carfax.org.uk> Date: Mon, 26 Aug 2013 21:39:46 -0600 Cc: linux-btrfs Message-Id: References: <5EB2ECAC-9A8C-4403-8630-944B646DE3B8@nickle.es> <6A12FF1B-5E1A-4F6F-92DA-41E52152E6F2@nickle.es> <20130826193110.GO3115@carfax.org.uk> To: Hugo Mills Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Aug 26, 2013, at 1:31 PM, Hugo Mills wrote: > > Let's assume that you don't have a physical device failure (which > is a different set of tools -- mount -odegraded, btrfs dev del > missing). > > First thing to do is to take a btrfs-image -c9 -t4 of the > filesystem, and keep a copy of the output to show josef. :) > > Then start with -orecovery and -oro,recovery for pretty much > anything. > > If those fail, then look in dmesg for errors relating to the log > tree -- if that's corrupt and can't be read (or causes a crash), use > btrfs-zero-log. > > If there's problems with the chunk tree -- the only one I've seen > recently was reporting something like "can't map address" -- then > chunk-recover may be of use. > > After that, btrfsck is probably the next thing to try. If options > -s1, -s2, -s3 have any success, then btrfs-select-super will help by > replacing the superblock with one that works. If that's not going to > be useful, fall back to btrfsck --repair. > > Finally, btrfsck --repair --init-extent-tree may be necessary if > there's a damaged extent tree. Finally, if you've got corruption in > the checksums, there's --init-csum-tree. This is helpful. Thanks. Chris Murphy