From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-34-i2.italiaonline.it ([212.48.25.206]:52489 "EHLO smtp-34.italiaonline.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750856AbaKZRSR (ORCPT ); Wed, 26 Nov 2014 12:18:17 -0500 Message-ID: <54760B89.3050604@inwind.it> Date: Wed, 26 Nov 2014 18:19:05 +0100 From: Goffredo Baroncelli Reply-To: kreijack@inwind.it MIME-Version: 1.0 To: Zygo Blaxell CC: linux-btrfs Subject: Re: BTRFS messes up snapshot LV with origin References: <546BA96D.4050805@ubuntu.com> <2A57F99C-80AA-4FD4-AA41-57F02AD4E1A2@colorremedies.com> <546CB531.2060509@ubuntu.com> <20141121042814.GR17395@hungrycats.org> <5470C92E.1070607@inwind.it> <20141123001927.GO17380@hungrycats.org> <5474AF87.6090702@inwind.it> <20141125202948.GP17380@hungrycats.org> <5474FBD9.5070709@inwind.it> <20141125222126.GQ17380@hungrycats.org> In-Reply-To: <20141125222126.GQ17380@hungrycats.org> Content-Type: text/plain; charset=windows-1252 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 11/25/2014 11:21 PM, Zygo Blaxell wrote: >> > However I still doesn't understood why you want btrfs-w/multiple disk over LVM ? > I want to split a few disks into partitions, but I want to create, > move, and resize the partitions from time to time. Only LVM can do > that without taking the machine down, reducing RAID integrity levels, > hotplugging drives, or leaving installed drives idle most of the time. > > I want btrfs-raid1 because of its ability to replace corrupted or lost > data from one disk using the other. If I run a single-volume btrfs > on LVM-RAID1 (or dm-RAID1, or RAID1 at any other layer of the storage > stack), I can detect lost data, but not replace it automatically from > the other mirror. OK, now I have understood. Anyway as workaround, take in account that you can pass explicitly the devices as: mount -o device=/dev/sda,device=/dev/sdb,device=/dev/sdc /dev/sdd /mnt (supposing that the filesystem is on /dev/sda.../dev/sdd) I am working to a mount.btrfs helper. The aim of this helper is to manage the assembling of multiple devices; the main points will be: - wait until all the devices appeared - allow (if required) to mount in degraded mode after a timeout - at this point it could/should also skip the lvm-snapshotted devices (but before I have to know how recognize these) I hope to issue the patches in the next week BR G.Baroncelli -- gpg @keyserver.linux.it: Goffredo Baroncelli Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5