Hi Brian, On Sun, 2012-10-07 at 12:37 -0400, Brian J. Murrell wrote: > I've exported some block devices to my initiators successful and the > initiators can see their "serial number" as such: > > # scsi_id -g /dev/sde > 3600140515ec87fad11c3d4a79daffbd3 > # scsi_id -g /dev/sdf > 3600140581c83070d4e69d4437db4ecdf > # scsi_id -g /dev/sdd > 3600140559468582d6b45d4db5d8fb5d5 > > Can I define on the target what these serial numbers will be? > So each virtual target device has a EVPD=80 Unit Serial that is used to build the modern EVPD=83 NAA IEEE Registered extended WWN designator value returned above to SCSI clients with scsi_id -g to uniquely identify SCSI devices across multiple fabric ports. This is automatically done via uuid in rtslib/targetcli code at device creation time, and can be optionally be disabled by passing generate_wwn=false at creation time as well. Note the underlying configfs attribute lives for each backend under /sys/kernel/config/target/core/$HBA/$DEV/wwn/vpd_unit_serial, so this typically will be an new UUID to ensure world-wide uniqueness. One possible scenario to set vpd_unit_serial explicitly is when sharing a single vpd_unit_serial across multiple target head-nodes representing the same shared storage device for active/active or active/passive operation. This is accomplished in rtslib python library code using rtslib.tcm.StorageObject._set_wwn(), see: http://www.risingtidesystems.com/doc/rtslib-gpl/html/rtslib.tcm.StorageObject-class.html --nab -- 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
