From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Stevens Subject: Re: [RFC] Persistent naming of scsi devices Date: Tue, 09 Apr 2002 18:16:53 -0700 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3CB39285.8000609@vitalstream.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: linux-scsi@vger.kernel.org Martin Peschke3 wrote: I'm going to wade in here. Based on my experiences on many other Unixish systems, wouldn't it be simply better to number the things based on controller position, SCSI ID, LUN and partition? This has been called "CTL" format in various documents, and many systems use this method such as Sun, DG AvIIons, DEC, HP and a host of others. E.g. "/dev/dsk/c0t1d2s3" is controller 0 (first SCSI controller seen on the bus), target ID 1, LUN 2, partition (slice) 3. Simple, unambiguous and repeatable. I understand that other devices may be seen on the PCI if you add or remove cards. Under this scheme, controller 0 is the first (lowest slot number) unit found. The next one would be controller 1. Even if you were to stuff, say, a video card in there, these would _still_ be the first SCSI cards found. The only time a change would occur is if a SCSI card was installed in a lower slot number or between other SCSI controllers (and only then if the original cards were left in) or if the ORDER of the cards was changed in the bus. As I said, other people smarter than I seem to think it makes sense. Why not Linux? It's silly to smush things together just to satisfy a bizzare craving to have a list of devices with no "holes" in it. Besides "fsck"ing or "mkfs"ing drives, how often do you refer to them by their names in "/dev", anyway? This would also work for tape drives. However, they're rooted at /dev/stape rather than /dev/dsk. At boot, you could create more mnemonic names as symbolic links to the CTL names if you wish (as is done with /dev/cdrom and such), but if you absolutely want to talk to the SAME DEVICE, you use the CTL name. Just adding my $0.02. We now return you to your regularly scheduled arguments. ---------------------------------------------------------------------- - Rick Stevens, SSE, VitalStream, Inc. rstevens@vitalstream.com - - 949-743-2010 (Voice) http://www.vitalstream.com - - - - su -; find / -name someone -exec touch \{\} \; - - - The UNIX way of touching someone - ----------------------------------------------------------------------