From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:43004 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757535Ab3FTNjw (ORCPT ); Thu, 20 Jun 2013 09:39:52 -0400 Date: Thu, 20 Jun 2013 21:39:42 +0800 From: Liu Bo To: Josef Bacik Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH 4/4] Btrfs-progs: exhance btrfs-image to restore image onto multiple disks Message-ID: <20130620133941.GA23098@localhost.localdomain> Reply-To: bo.li.liu@oracle.com References: <1371729930-22497-1-git-send-email-bo.li.liu@oracle.com> <1371729930-22497-5-git-send-email-bo.li.liu@oracle.com> <20130620122432.GA4288@localhost.localdomain> <20130620123919.GB4288@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20130620123919.GB4288@localhost.localdomain> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, Jun 20, 2013 at 08:39:19AM -0400, Josef Bacik wrote: > On Thu, Jun 20, 2013 at 08:24:32AM -0400, Josef Bacik wrote: > > On Thu, Jun 20, 2013 at 08:05:30PM +0800, Liu Bo wrote: > > > This adds a 'btrfs-image -m' option, which let us restore an image that > > > is built from a btrfs of multiple disks onto several disks altogether. > > > > > > This aims to address the following case, > > > $ mkfs.btrfs -m raid0 sda sdb > > > $ btrfs-image sda image.file > > > $ btrfs-image -r image.file sdc > > > --------- > > > so we can only restore metadata onto sdc, and another thing is we can > > > only mount sdc with degraded mode as we don't provide informations of > > > another disk. And, it's built as RAID0 and we have only one disk, > > > so after mount sdc we'll get into readonly mode. > > > > > > > Um that shouldn't be happening, the restore will mask out the RAID parts of the > > chunk tree and it should work just fine. Are you using the most recent version > > of btrfs-image? If this is happening it's a bug and we need to fix it, but I've > > restored several file systems from users with raid0/10 file systems onto a > > single disk and it's worked just fine. Thanks, > > > > Well apparently I've been hallucinating because it definitely doesn't work. I'd > rather fix the device tree so it only restores onto one disk, since the raid > level shouldn't matter and it does in fact get masked out. So the only thing > left would be to fix the device tree so the only device it knows about is the > device we're restoring to. Thanks, Um, I believe that'd work and it's not hard, but I'm afraid that way we're not able to debug bugs related to raid types? thanks, liubo