From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Phillips Subject: Re: [RFD] Incremental fsck Date: Sat, 12 Jan 2008 15:55:53 -0800 Message-ID: <200801121555.54533.phillips@phunq.net> References: <200801090022.55589.a1426z@gawab.com> <60808.198.182.194.170.1199827911.squirrel@clueserver.org> <20080109091656.GL3351@webber.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Alan , Al Boldi , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Andreas Dilger Return-path: Received: from phunq.net ([64.81.85.152]:34659 "EHLO moonbase.phunq.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751645AbYALX4F (ORCPT ); Sat, 12 Jan 2008 18:56:05 -0500 In-Reply-To: <20080109091656.GL3351@webber.adilger.int> Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wednesday 09 January 2008 01:16, Andreas Dilger wrote: > While an _incremental_ fsck isn't so easy for existing filesystem > types, what is pretty easy to automate is making a read-only snapshot > of a filesystem via LVM/DM and then running e2fsck against that. The > kernel and filesystem have hooks to flush the changes from cache and > make the on-disk state consistent. > > You can then set the the ext[234] superblock mount count and last > check time via tune2fs if all is well, or schedule an outage if there > are inconsistencies found. > > There is a copy of this script at: > http://osdir.com/ml/linux.lvm.devel/2003-04/msg00001.html > > Note that it might need some tweaks to run with DM/LVM2 > commands/output, but is mostly what is needed. You can do this now with ddsnap (an out-of-tree device mapper target) either by checking a local snapshot or a replicated snapshot on a different machine, see: http://zumastor.org/ Doing the check on a remote machine seems attractive because the fsck does not create a load on the server. Regards, Daniel