From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Borzenkov Date: Fri, 02 Nov 2007 04:44:59 +0000 Subject: Re: scsi_id question Message-Id: <200711020745.00243.arvidjaar@mail.ru> MIME-Version: 1 Content-Type: multipart/mixed; boundary="===============1197567695==" List-Id: References: In-Reply-To: To: linux-hotplug@vger.kernel.org --===============1197567695== Content-Type: multipart/signed; boundary="nextPart1831166.C5xvrrZnEl"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit --nextPart1831166.C5xvrrZnEl Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Friday 02 November 2007, lemons_terry@emc.com wrote: > Hi > > We've been observing the behavior of scsi_id, as a component of the udev > machinery that creates persistent device names in the > /dev/|generic|disk|tape/by-id directories. When scsi_id is run against a > tape device that has more than one useful item in the VPD pages, scsi_id > selects one of these items as the basis for the name that is generated.=20 > There is obviously some sort of hierarchy in play here. For instance, if= a > device has both a WWNN and a serial number, scsi_id will use the WWNN.=20 > That's a good choice, IMHO, given that modern tape libraries have WWNN > assigned to the 'sled' that tape drives fit into When a tape drive is > replaced, the serial number changes but the 'sled' WWNN stays the same (so > I'm told). > > But if a device has both an IENN and a serial number, the IENN is used.=20 > And that's a bad choice, because the IENN is not unique.=20 But is not duplicated EUI-64 actually a bug that should be reported to vend= or? > I have a tape=20 > library in my lab that has two tape drives with the same IENN and differe= nt > serial numbers. udev does not create a persistent device name for both of > these tape drives. This is, to me, a bug. > > Can I/we get a peek at the hierarchy that scsi_id uses?=20 Sure. In udev sources :) > Methinks some=20 > fine-tuning is necessary. > By default page 0x83 is tried first if available. You can force page 0x80=20 (serial number) when calling scsi_id or per vendor or per model=20 in /etc/scsi_id.config. HTH =2Dandrey --nextPart1831166.C5xvrrZnEl Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) iD8DBQBHKqtMR6LMutpd94wRAjRJAJ4hli7qTxkwC/mO3DZ/MolC6bK5QACg1B/W 8EEYvaJk5kDa8Qxf7RrJc5M= =YemN -----END PGP SIGNATURE----- --nextPart1831166.C5xvrrZnEl-- --===============1197567695== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ --===============1197567695== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel --===============1197567695==--