From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH 13/18] libmultipath: add ignore_new_boot_devs option Date: Mon, 12 Oct 2015 09:08:17 +0200 Message-ID: <561B5C61.6010201@suse.de> References: <1444333491-16265-1-git-send-email-bmarzins@redhat.com> <1444333491-16265-14-git-send-email-bmarzins@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1444333491-16265-14-git-send-email-bmarzins@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: dm-devel@redhat.com List-Id: dm-devel.ids On 10/08/2015 09:44 PM, Benjamin Marzinski wrote: > When multipath relies on the wwids file to determine whether a device is > a multipath path (with "multipath -c"), it will fail the first time a > new multipathable device is discovered, since the wwid clearly won't be > in the wwids file. This is usually fine. Multipath will still set > itself up on the device, and add the wwid to the wwids file. However, > this causes a race, where multipath won't claim the path immediately, > and something else may. Later multipath will try, and possibly succeed > at, setting itself up on that device. > = > I've seen cases where this can cause problems during boot on and > immediately after install, where multipath racing with LVM on an already > labelled device can get the machine into a state where boot fails. This > can be avoided if multipath simply doesn't set itself up on any devices > that it didn't claim (with "multipath -c") in the initramfs. It can > still safely attempt to set itself up on these devices later in boot, > after the regular filesystem has been set up. > = > To allow this, this patch adds a new option, ignore_new_boot_devs. When > enabled, this patch simply keeps multipath from being set up on devices > that aren't already in the wwids file (along with all the other checks > that multipath already does). This means that only devices that are > claimed by "multipath -c" will be used by multipath. > = > Signed-off-by: Benjamin Marzinski > --- Well, as SUSE is not relying on /etc/wwids during boot we don't have this issue :-) Reviewed-by: Hannes Reinecke Cheers, Hannes -- = Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: F. Imend=F6rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N=FCrnberg)