On 10/01/2015 06:25 PM, David Disseldorp wrote: > On Thu, 01 Oct 2015 07:42:13 +0200, Hannes Reinecke wrote: > >>> Would there be any benefit in making this a per-target, per-tpg, or >>> per-lun attribute? (I can't think of any but wanted to raise the >>> question.) >>> >> The vendor ID is describing the target implementation. >> And it'll be rather hard to have different implementations for LUNs >> being exported from the same host ... >> >> We need to be careful to not clutter the vendor ID namespace. >> Most OS uses it to distinguish target implementation details >> (think of multipathing) and it will become an absolute mess >> if we have different vendor ID per LUN, all using the same >> implementations. > > The inquiry PRODUCT IDENTIFICATION (model) and PRODUCT REVISION LEVEL > fields can currently differ across LUs with differing backstores. To > remain consistent with these fields, it may make sense to also allow > VENDOR ID changes on a per LU basis. > > SPC-4 (r37) isn't very clear: > 6.6.2 Standard INQUIRY data > ... > The T10 VENDOR IDENTIFICATION field contains eight bytes of > left-aligned ASCII data (see 4.3.1) identifying the manufacturer of > the logical unit. > > 7.8.6.4 T10 vendor ID based designator format > ... > The T10 VENDOR IDENTIFICATION field contains eight bytes of > left-aligned ASCII data (see 4.3.1) identifying the manufacturer of > the product. > Of course they can per standard. I'm not doubting that. However, the fact is that the vendor ID / product ID is used by the host OS to identify the target implementation, and it would be very hard to have different target implementations running on the same OS ... Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
