From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luben Tuikov Subject: Re: generating a Linux WWN? Date: Wed, 3 Oct 2007 12:44:17 -0700 (PDT) Message-ID: <983400.77431.qm@web31814.mail.mud.yahoo.com> References: <4703DADF.70509@garzik.org> Reply-To: ltuikov@yahoo.com Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from web31814.mail.mud.yahoo.com ([68.142.206.167]:39721 "HELO web31814.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752791AbXJCToT (ORCPT ); Wed, 3 Oct 2007 15:44:19 -0400 In-Reply-To: <4703DADF.70509@garzik.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Jeff Garzik , Matthew Jacob Cc: ltuikov@yahoo.com, Michael Reed , James.Smart@emulex.com, linux-scsi --- Jeff Garzik wrote: > Matthew Jacob wrote: > >> The generation algorithm is whatever makes people happy. I would > >> probably pick a fixed prefix like 0x6C 0x69 0x63 ("lin"), something that > >> doesn't conflict with IEEE org ids for a long time to come. Then, > >> get_random_bytes() or hash some useful machine characteristics for the > >> rest of the bytes. > > > > The "probably" here is kind of amusing. > > > > Look, Linux development has the moolah (look at all the money IBM and > > SGI and others have shoveled in)- why don't you get a Linux block of > > OUIs from the IEEE and set up an RSS-like feed so the Open Source > > community can get WWNs with that OUI and a incrementing serial number > > as needed- that would be a *real* service. I've thought about doing > > this, but I'd have to fork over at least 1700$USD to get an official > > IEEE OUI and over the last ten years I've already spent far too much > > of my own money on open source support. > > > > Heck, maybe even the IEEE would comp you on OUIs. > > Certainly, I would love for this to happen! Although my employer (Red > Hat), SGI, IBM or whomever might be willing to tackle this, it might be > more appropriate for the Linux Foundation. > > Anybody wanna volunteer to pursue this? SAS WWN have nothing to do with Linux. The kernel should not generate SAS WWN and assign them to SAS initiator ports. SAS WWNs should be given to SAS initiator ports and SAS target ports by a storage management application which maintains and configures the storage domain, zoning, permissions, connectivity, etc. What is needed is persistence, regardless of reboots of what OS is running on the host CPU/system. SAS WWNs are properties of the SAS target/initiator port, they are not properties of when the host system was booted, or what OS is running on it. Think about it this way: you don't change your name every morning you wake up and MAC addresses are not generated by the kernel for a network device which has none. Those are persistent across reboots or type of host OS. Luben