From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Wilck Subject: mke2fs with discard option breaks RAID5 array Date: Sat, 14 Sep 2013 21:50:22 +0200 Message-ID: <5234BDFE.7050700@arcor.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid List-Id: linux-raid.ids I just had the following weird effect under OpenSUSE 12.3, kernel 3.7.10-1.16. I am wondering if it's a known problem. Creating a RAID5 array (format doesn't seem to matter) either with the openSUSE native mdadm 3.2.6 or mdadm 3.3, and running mke2fs on it, fails. The RAID array is broken after that, all disks faulty, any IO fails. Further examination shows that the problem is related to mke2fs trying to discard blocks. Running "-E nodiscard" or setting "discard=no" in mke2fs.conf fixes the problem. Unfortnately, "discard" seems to be the default. Details under https://bugzilla.novell.com/show_bug.cgi?id=840413 Has anyone seen this before? Martin