From: Simon Matthews Subject: Re: Filesystem size problem. Date: Mon, 12 Dec 2016 18:48:44 -0800 Message-ID: References: <6B4536F9-A059-45AC-8A14-85879FC4AC79@dilger.ca> <46f8665e-c3b5-b2e9-346b-4bbb380bb6e2@redhat.com> <7393F8E6-AD83-430E-AE3E-A800DAB91FD3@dilger.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 To: linux-ext4@vger.kernel.org Return-path: Received: from mail-qk0-f172.google.com ([209.85.220.172]:34079 "EHLO mail-qk0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752880AbcLMCsq (ORCPT ); Mon, 12 Dec 2016 21:48:46 -0500 Received: by mail-qk0-f172.google.com with SMTP id q130so103595054qke.1 for ; Mon, 12 Dec 2016 18:48:46 -0800 (PST) In-Reply-To: <7393F8E6-AD83-430E-AE3E-A800DAB91FD3@dilger.ca> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Dec 12, 2016 at 2:36 PM, Andreas Dilger wrote: > On Dec 9, 2016, at 9:35 PM, Eric Sandeen wrote: >> >> On 12/9/16 2:29 PM, Andreas Dilger wrote: >>> On Dec 8, 2016, at 10:40 PM, Simon Matthews wrote: >>>> >>>> I have an ext3 filesystem that will not mount under newer versions of >>>> the kernel and I hope someone here can help. >>>> >>>> Obviously, one solution is "backup and re-create from scratch". I have >>>> the backups, but I hope that there may be a quicker method to fix the >>>> issues. >>>> >>>> The root issue is that the filesystem is very slightly smaller than >>>> the allocated space. >> >> So the device is now smaller than the filesystem thinks, right? >> >>> The filesystem exists on a MDRAID device and I >>>> think that when I converted the MDRAID to a newer metadata version, it >>>> truncated the available size, slightly. However, how I got here isn't >>>> really important, fixing it now is. >>> >>> Running "e2fsck -fy" should fix this. I'd recommend to use the latest >>> version of e2fsck. >> >> Reaslly? e2fsck can change total blocks in the superblock to accomodate a >> shrunken device? That's a new one for me... > > Strange, I thought this case was handled properly by e2fsck. > > You could probably fix this with: > > # debugfs -R "ssv blocks_count 693359326" /dev/md5 "probably"? How safe or dangerous is this? Does the filesystem have to be unmounted first? Simon