From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: Reassemble Raid 6 Date: Mon, 10 Feb 2014 18:02:54 -0500 Message-ID: <52F95A9E.2060805@turmel.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Justin Stephenson , linux-raid@vger.kernel.org List-Id: linux-raid.ids On 02/10/2014 07:13 PM, Justin Stephenson wrote: > Hello Phil, > > You are 100% correct. Thanks for your email. I had 2 separate ARRAY > entries in my mdadm.config file. When I added the spare, I added the new > information to the config file but did not remove the old entry. Total > newbie mistake. > > - I commented out all the previous entries in the mdadm.config file (it > had a devices lists instead of the UUID information) > > - I successfully assembled the array (mdadm --assemble /dev/md0 > /dev/sdb1 etc...) > > - I updated the config file using the information from mdadm -Esc > partitions | grep UUID and deleted the old entries. > > - I uncommented the fstab entry for the array and rebooted. > > > Everything is working perfectly now. > > > I remember reading somewhere that mdadm can run without the config file > by using the RAID uuid and the information in the superblocks. Would > this be more reliable? > > Thanks Again You're welcome. I suggest you trim the mdadm.conf file even further--I only specify name and uuid, so device changes don't interfere with assembly. Like so (slightly edited): MAILFROM mdadm@example.com MAILADDR philip@example.com DEVICE /dev/sd[a-z][1-9] # Mirrored Boot partitions ARRAY /dev/md1 UUID=75c011c6:caeb06ea:ec7e3370:aa4f3320 # Far mirror (Raid10) core operations ARRAY /dev/md2 UUID=6b4858da:f24e2567:34e73fe5:b8f2c118 # Bulk redundant (Raid6) storage ARRAY /dev/md3 UUID=04f3706c:79a3cd73:8a558eee:93ec1879 HTH, Phil ps. Don't forget to update your initramfs after any changes to mdadm.conf!