From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christopher White Subject: Re: mdadm does not create partition devices whatsoever, "partitionable" functionality broken Date: Fri, 13 May 2011 19:32:23 +0200 Message-ID: <4DCD6B27.70402@pulseforce.com> References: <4DCD4A83.8060202@pulseforce.com> <4DCD6119.3080705@turmel.org> <4DCD67EF.1070602@pulseforce.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4DCD67EF.1070602@pulseforce.com> Sender: linux-raid-owner@vger.kernel.org To: Phil Turmel Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids I forgot to mention that I've also tried "sudo fdisk /dev/md1" and creating two partitions that way. It fails too. This leads me to conclude that /dev/md1 was never created in partitionable mode and that the kernel refuses to create anything beyond a single partition on it. On 5/13/11 7:18 PM, Christopher White wrote: > Hi Phil, thanks for the response! > > On 5/13/11 6:49 PM, Phil Turmel wrote: >> Hi Christopher, >> >> On 05/13/2011 11:13 AM, Christopher White wrote: >>> Greetings. >>> >>> I have spent TEN hours trying everything other than regressing to a >>> REALLY old version. I started out on 3.1.4 and have also tried >>> manually upgrading to 3.2.1, but the bug still exists. >>> >>> Somewhere along the way, the "auto" partitionable flag has broken. >>> >>> sudo mdadm --create --level=raid5 --auto=part2 /dev/md1 >>> --metadata=1.2 --raid-devices=4 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2 >>> >>> This only creates /dev/md1. It is of course possible to create one >>> big partition as /dev/md1p1 with any partitioning program, but >>> FORGET about trying to create /dev/md1p2. >> What exactly did fdisk or parted report when you tried to partition >> /dev/md1 ? > I run "sudo gparted /dev/md1" to access the whole RAID array, since I > like the GUI for precisely creating partitions. When making two ext4 > partitions and applying the changes, it successfully creates > /dev/md1p1 (which does not exist before this operation is performed). > It then goes on to trying to create md1p2 and it sends the commands to > the md1 device, but md1p2 is never created. After the step of creating > the partition (which failed, but gparted does not know that), it tries > to set up the file system, which fails since there is no md1p2: > mkfs.ext4 -j -O extent -L "" /dev/md1p2 > "mke2fs 1.41.14 (22-Dec-2010) > Could not stat /dev/md1p2 --- No such file or directory" >>> The problem is that the RAID array is NOT created in partitionable >>> mode, and only supports one large partition, despite ALL attempts at >>> EVERY format of the --auto option, you name it, -a part2, >>> --auto=mdp2, --auto=part2, --auto=p2, --auto=mdp, --auto=part, >>> --auto=p, --auto=p4, you name it and I've tried it! >>> >>> My guess is the functionality of creating partitionable arrays >>> literally DID break somewhere prior to/at version 3.1.4 which is the >>> earliest version I tried. >> The mdadm<==> kernel interface for this might be broken, but as a >> side-effect of the change to make all md devices support conventional >> partition tables. I don't recall exactly when this changed, but it >> was several kernels ago. >> >> What kernel are you running? > Linux Mint 11 RC, which uses 2.6.38-8-generic. >>> I'm giving up and creating physical n-1 sized partitions on the >>> source disks and creating two RAID 5 arrays from those partitions >>> instead, but decided I really MUST report this bug so that other >>> people don't bang their head against the wall for ten hours of their >>> life as well. ;-) >> Consider trying "mdadm --create" without the "--auto" option at all, >> then fdisk on the resulting array. >> >> Phil > I've tried that as well during my testing since some postings > suggested that leaving out the option will create a partitionable > array, but it didn't. > > > Christopher