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Date:   Mon, 4 Jun 2018 14:48:30 +0200
From:   Johannes Thumshirn <jthumshirn@suse.de>
To:     Sagi Grimberg <sagi@grimberg.me>
Cc:     Mike Snitzer <snitzer@redhat.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Christoph Hellwig <hch@lst.de>,
        Keith Busch <keith.busch@intel.com>,
        Hannes Reinecke <hare@suse.de>,
        Laurence Oberman <loberman@redhat.com>,
        Ewan Milne <emilne@redhat.com>,
        James Smart <james.smart@broadcom.com>,
        Linux Kernel Mailinglist <linux-kernel@vger.kernel.org>,
        Linux NVMe Mailinglist <linux-nvme@lists.infradead.org>,
        Martin George <marting@netapp.com>,
        John Meneghini <John.Meneghini@netapp.com>, axboe@kernel.dk
Subject: Re: [PATCH 0/3] Provide more fine grained control over multipathing
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On Mon, Jun 04, 2018 at 02:46:47PM +0300, Sagi Grimberg wrote:
> I agree with Christoph that changing personality on the fly is going to
> be painful. This opt-in will need to be one-host at connect time. For
> that, we will probably need to also expose an argument in nvme-cli too.
> Changing the mpath personality will need to involve disconnecting the
> controller and connecting again with the argument toggled. I think this
> is the only sane way to do this.

If we still want to make it dynamically, yes. I've raised this concern
while working on the patch as well.

> Another path we can make progress in is user visibility. We have
> topology in place and you mentioned primary path (which we could
> probably add). What else do you need for multipath-tools to support
> nvme?

I think the first priority is getting nvme notion into multipath-tools
like I said elsewhere and then see. Martin Wilck was already working
on patches for this.

-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
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