From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Subject: Re: [PATCH 0/1] RFC: Use /dev/md/X as default name Date: Mon, 02 Mar 2015 11:32:16 -0500 Message-ID: References: <1423684389-10977-1-git-send-email-Jes.Sorensen@redhat.com> <20150219083708.2ab46006@notabene.brown> <20150219093236.25660678@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20150219093236.25660678@notabene.brown> (NeilBrown's message of "Thu, 19 Feb 2015 09:32:36 +1100") Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids NeilBrown writes: > On Wed, 18 Feb 2015 17:11:33 -0500 Jes Sorensen > wrote: > >> NeilBrown writes: >> > On Wed, 18 Feb 2015 13:12:09 -0500 Jes Sorensen >> > wrote: >> > >> >> Jes.Sorensen@redhat.com writes: >> >> > From: Jes Sorensen >> >> > >> >> > I have received some issues for when creating an array using a >> >> > /dev/mdX name, the matching symlink in /dev/md/X isn't >> >> > created. Whereas if you create /dev/md/X, /dev/mdX is created >> >> > automatically. >> >> > >> >> > I was trying to see if there was a better way of dealing with this, >> >> > but I couldn't find one. If you have suggestions for a better solution >> >> > I am all ears. >> >> > >> >> > Thoughts? >> >> >> >> Hi Neil, >> >> >> >> Any thoughts on this one? >> > >> > Thanks for the reminder.... >> > >> > I'm not sure that I really see the problem. >> > >> > "I ask it to create /dev/mdX and it doesn't create /dev/md/X". >> > >> > Well ... no. You didn't ask it to. If you want it to create /dev/md/X, >> > then ... ask it to. >> > >> > /dev/mdX is the canonical name. It always gets created. >> > /dev/md/X is a convenient alias. It gets created if requested. >> > >> > Is there really a problem here worth solving? >> > >> > Maybe I missed something. >> >> I have had complaints in Fedora from the installer people that they rely >> on the /dev/md/ name being created when they create a new device. It is >> also inconsistent because /dev/md/ will be created if you run >> 'mdadm -As' later on. > > If they rely on the /dev/md/ name being created, then surely they should ask > for it to be created. > Is it really harder to run "mdadm -C /dev/md/0" than "mdadm -C /dev/md0" ?? > > If you create an array as "/dev/md0", then after subsequent "mdadm > -As" /dev/md0 will exist. > If you create an array as "/dev/md/0", then after subsequent mdadm > -As", /dev/md/0 will exist. > > The fact that something unasked for also exists is a bonus. > >> >> I don't see it as a major issue, but I can see why it is frustrating for >> some and I think there is something to be said for being consistent in >> behavior. > > I think the behaviour is perfectly consistent. It just follows rules that > are slightly less trivial that some people appear to want. > > However.... > If you changed > > mp = map_by_uuid(&map, info->uuid); > if (mp && mp->path && > strncmp(mp->path, "/dev/md/", 8) == 0) { > printf("MD_DEVNAME="); > print_escape(mp->path+8); > putchar('\n'); > } > > > in Detail.c so that when mp->path were "/dev/md0", MD_DEVNAME became "0", > then you should get the result that you are after, and I probably wouldn't > object to the patch. Neil, Finally had time to go back and look at this - I don't quite understand your request here. As far as I can see, the above code isn't run at all during device creation, so I don't get how modifying it as you suggest will make /dev/md/111 appear if I create /dev/md111? Cheers, Jes