From: Kevin Shanahan Subject: Ext4 external journal UUID mismatch? Date: Mon, 16 Jul 2012 09:10:58 +0930 Message-ID: <20120715234058.GA2562@tuon.disenchant.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: linux-ext4@vger.kernel.org Return-path: Received: from ipmail06.adl2.internode.on.net ([150.101.137.129]:53436 "EHLO ipmail06.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752399Ab2GOXlE (ORCPT ); Sun, 15 Jul 2012 19:41:04 -0400 Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi, I have created some filesystems with external journals, and after reboot (clean shutdown) these will not mount anymore. I see in dmesg: [42214.365496] EXT4-fs (dm-10): journal UUID does not match However, the UUIDs look fine when viewed with dumpe2fs: # dumpe2fs -h /dev/it8/nfs-kvmhost0 Filesystem volume name: Last mounted on: /srv/nfs4/kvmhost0-rootfs Filesystem UUID: 8a543c99-8a66-4ec2-9664-e82e3642cee0 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index filetype extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize Filesystem flags: signed_directory_hash Default mount options: journal_data user_xattr acl Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 983040 Block count: 3932160 Reserved block count: 196608 Free blocks: 3628551 Free inodes: 939811 First block: 0 Block size: 4096 Fragment size: 4096 Reserved GDT blocks: 959 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 RAID stride: 128 RAID stripe width: 768 Flex block group size: 16 Filesystem created: Sun Jul 8 10:45:26 2012 Last mount time: Sun Jul 8 10:45:26 2012 Last write time: Sun Jul 15 20:47:20 2012 Mount count: 1 Maximum mount count: -1 Last checked: Sun Jul 8 10:45:26 2012 Check interval: 0 () Lifetime writes: 2024 MB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal UUID: 9e21ab2e-533e-41b1-a006-21bcf7574a45 Journal device: 0xfd0c Default directory hash: half_md4 Directory Hash Seed: 61c03a7c-947b-4432-a134-7b0dfd307228 # dumpe2fs -h /dev/ssdvg/jnl-kvmhost0 Filesystem volume name: Last mounted on: Filesystem UUID: 9e21ab2e-533e-41b1-a006-21bcf7574a45 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: journal_dev Default mount options: user_xattr acl Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 0 Block count: 262144 Reserved block count: 0 Free blocks: 0 Free inodes: 0 First block: 0 Block size: 4096 Fragment size: 4096 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 0 Inode blocks per group: 0 Filesystem created: Sun Jul 8 10:45:20 2012 Last mount time: n/a Last write time: Sun Jul 8 10:45:21 2012 Mount count: 0 Maximum mount count: -1 Last checked: Sun Jul 8 10:45:20 2012 Check interval: 0 () Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Default directory hash: half_md4 Directory Hash Seed: 9f3616f0-a8e2-4e61-8e31-2632a0fb2287 Journal block size: 4096 Journal length: 262144 Journal first block: 2 Journal sequence: 0x000120d6 Journal start: 0 Journal number of users: 1 Journal users: 8a543c99-8a66-4ec2-9664-e82e3642cee0 I don't understand why mount/kernel unhappy with this. Can someone shed some light on this? # uname -r 3.4.4-3-ARCH Thanks, Kevin.