[dm-devel] multipath: add find_multipaths feature.

[Peter Volkov]

В Чтв, 14/07/2011 в 20:53 -0400, Mike Snitzer пишет:
> On Tue, Dec 07 2010 at  6:00pm -0500,
> Christophe Varoqui <christophe.varoqui at gmail.com> wrote:
> 
> > On mar., 2010-11-16 at 17:25 -0600, Benjamin Marzinski wrote:
> > > This adds a new default feature, find_multipaths. When this is set to yes,
> > > multipath will no longer try to create multipath devices using every
> > > non-blacklisted device. Instead, it will only create a device when one of
> > > three conditions are met.
> > > 
> > > 1. Three are at least two non-blacklisted paths with the same wwid
> > > 2. The user manually forces the creation, by specifying a device with the
> > >    multipath command.
> > > 3. A path has the same wwid as a multipath device that was previously crreated
> > >    (even if that multipath device doesn't currently exist).
> > > 
> > > To do 3, multipath stores the wwid of every path that it creates in
> > > /etc/multipath/wwids. Whenever a path is added, its wwid is checked against
> > > this file.  If there's a match, it is multipathed, even if it's the only path.
> > > This should allow multipath to automatically choose the correct paths to make
> > > into multipath devics in most cases, without needing the user to edit the
> > > blacklist.

Is it good idea to store such information in /etc? /etc is supposed to
be ro and known violators, e.g. /etc/mtab, afair are going to be moved
into /run.

--
Peter.