From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 1/2] scsi_transport_fc: implement 'disable_target_scan'
	module parameter
Date: Wed, 2 Mar 2016 10:18:42 +0100
Message-ID: <20160302091842.GD1308@lst.de>
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To: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>, "Martin K . Petersen" <martin.petersen@oracle.com>, James Bottomley <james.bottomley@hansenpartnership.com>, Johannes Thumshirn <jthumshirn@suse.com>, linux-scsi@vger.kernel.org

On Wed, Mar 02, 2016 at 01:59:39PM +0800, Hannes Reinecke wrote:
> Main reasons being that
> a) it's most commonly on FC where you end up having thousands of LUNs;
> SAS domains are of finite size and you'd need to string quite a few SAS
> expanders together to achieve a similar setup. And iSCSI is ... well.
> b) FC already has the required infrastructure in place where you easily
> can suppress a target scan, making the patch really trivial.
> 
> So rather than trying to come up with a generic solution and an overly
> complicated patch I opted for the simpler version :-)

Having a global disable just for all FC is still odd.  Either you
do it for all devices and always initiate a manual scan, or you
need to do it on a per-host basis somehow.