From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nigel J. Terry" Subject: Re: Raid5 reshape Date: Fri, 16 Jun 2006 12:00:49 -0400 Message-ID: <4492D5B1.60004@nigelterry.net> References: <449250ED.7090302@irule.net> <17554.21119.487820.638171@cse.unsw.edu.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <17554.21119.487820.638171@cse.unsw.edu.au> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown , linux-raid@vger.kernel.org Cc: Tim List-Id: linux-raid.ids Neil Brown wrote: > On Thursday June 15, irule@irule.net wrote: > >> Hello all, >> >> I'm sorry if this is a silly question, but I've been digging around for >> a few days now and have not found a clear answer, so I'm tossing it out >> to those who know it best. >> >> I see that as of a few rc's ago, 2.6.17 has had the capability of adding >> additional drives to an active raid 5 array (w/ the proper ver of mdadm, >> of course). I cannot, however, for the life of me find out exactly how >> one goes about doing it! I would love if someone could give a >> step-by-step on what needs to be changed in, say, mdadm.conf (if >> anything), and what args you need to throw at mdadm to start the reshape >> process. >> >> As a point of reference, here's my current mdadm.conf: >> >> >> DEVICE /dev/sda1 >> DEVICE /dev/sdb1 >> DEVICE /dev/sdc1 >> ARRAY /dev/md0 devices=/dev/sda1,/dev/sdb1,/dev/sdc1 level=5 num-devices=3 >> >> > > May I suggest: > > DEVICE /dev/sd?1 > ARRAY /dev/md0 UUID=whatever > > it would be a lot safer. > > >> I will be adding the devices /dev/sde1 and /dev/sdf1 (when I can find >> out how :) >> > > mdadm /dev/md0 --add /dev/sde1 /dev/sdf1 > mdadm --grow /dev/md0 --raid-disks=5 > > NeilBrown > - > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > > This might be an even sillier question, but I'll ask it anyway... If I add a drive to my RAID5 array, what happens to the ext3 filesystem on top of it? Does it grow automatically? Do I have to take some action to use the extra space? Thanks Nigel