From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luben Tuikov Subject: Re: Should sd REALLY allocate a device for an offline device Date: Fri, 14 Mar 2003 14:33:59 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3E722EA7.7040802@splentec.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: List-Id: linux-scsi@vger.kernel.org To: Steve Brueggeman Cc: linux-scsi@vger.kernel.org Steve Brueggeman wrote: > There's a managed storage device that reports 0x20 in byte 0 of the > Inquiry data, which means it's a SCSI_DISK, but the LUN is detached. The physical device is not currently attached to the LU, but the device is supported and we know a fait bit about it from the INQUIRY data. > scan_scsis_single() acknowledgs this, and marks the device as not > online, and lets the upper level device drivers decide what to do. This is the right thing to do. > It is my belief that if a device is not online, the scsi disk driver > should not allocate a device slot for it. See the following simple > patch. Any thoughts? It seems obvious to me, but maybe I'm missing > something. As was already answered, a device being ``offline'' doesn't mean that's it's not there. In the simplest terms it means that the LU device server cannot process any commands addressed to the physical device at this moment. -- Luben