From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wp216.webpack.hosteurope.de ([80.237.132.223]:51806 "EHLO wp216.webpack.hosteurope.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751356AbcCOV7e (ORCPT ); Tue, 15 Mar 2016 17:59:34 -0400 From: Andreas Grosse To: linux-btrfs@vger.kernel.org Subject: Incompat features: raid56 ... when creating a RAID6? Date: Tue, 15 Mar 2016 22:42:29 +0100 Message-ID: <16570443.SxVegaKaET@andilaptop> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hello everyone! I just wanted to create a RAID6 and got the following output: > # mkfs.btrfs -d raid6 -m raid6 -L slowPool /dev/sd[cdefgh] > btrfs-progs v4.4.1 > See http://btrfs.wiki.kernel.org for more information. > > Label: slowPool > UUID: 85ddf6a7-51f1-4cc0-b6cd-d472277b0e86 > Node size: 16384 > Sector size: 4096 > Filesystem size: 27.29TiB > > Block group profiles: > Data: RAID6 4.01GiB > Metadata: RAID6 4.01GiB > System: RAID6 14.50MiB > > SSD detected: no > Incompat features: extref, raid56, skinny-metadata > Number of devices: 6 > > Devices: > ID SIZE PATH > > 1 4.55TiB /dev/sdc > 2 4.55TiB /dev/sdd > 3 4.55TiB /dev/sde > 4 4.55TiB /dev/sdf > 5 4.55TiB /dev/sdg > 6 4.55TiB /dev/sdh And then the line saying "Incompat features: ... raid56" came to my eyes. Reading the corresponding manpage, it says: > raid56 > extended format for RAID5/6, also enabled if raid5 or raid6 block groups > are selected So why is raid56 marked as incompatible if I just created a file system with multiple disks using the RAID6 profile? Have I misunderstood something there? I am confused. Can somebody here lighten this up? (If important: Gentoo Linux with kernel 4.5.0, btrfs-progs v4.4.1) Andi{.n++%ݶw{.n+{k~^nrzh&zzޗ++zfh~iz_j:+v)ߣm