From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: mdadm ddf questions Date: Thu, 3 Mar 2011 09:31:36 +1100 Message-ID: <20110303093136.586df7e7@notabene.brown> References: <4D5FA5C4.8030803@gmail.com> <4D63688E.5030501@gmail.com> <20110223171712.09509f9e@notabene.brown> <4D67ECA2.2020201@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4D67ECA2.2020201@gmail.com> Sender: linux-raid-owner@vger.kernel.org To: Albert Pauw Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Fri, 25 Feb 2011 18:53:38 +0100 Albert Pauw wrote: > Hi Neil, > > I investigated a bit further, and here are my findings: > > Looking at /proc/mdstat I see the following: > > - When I create a ddf containter with a name (say /dev/md0), I stop it > and start it again, the name has always changed to /dev/md127, > don't know if this is intentional. It is intentional. Numbers aren't really meaningful for ddf containers. mdadm should also create /dev/md/ddf0 as well which points to md127 and I consider 'ddf0' to be the 'official' name. I hope to make the 'md127' disappear eventually. > - After creating the containter, all disks are marked as spare, > designated with the (S) ending. However, when I put a disk in an array, it > still stays marked as (S) in the containter entry in /proc/mdstat. I > think those disks should be branded (S) anymore. Yes, the (S) in the container is a bit misleading. It simply means that the device isn't active in 'this' array - which is true because the container isn't really an active array. I've made a note to tidy this up at some stage. > I also noticed that a RAID5 array created in a containter cannot be > expanded with another disk (option -G) as it can in normal setup (i.e. > without using the container). > The same hold for a RAID1 where you cannot add a third disk. Yes.. ddf support is really still quite preliminary. While reshaping arrays should be possible it requires quite a bit of coding in mdadm which it is hard to get motivated about ..... > > I hope this gives you more clues about a possible fix? Yes, very helpful. I hope to fix the bugs in a week or so. The missing features will take longer. Thanks, NeilBrown