Here is the code snippet for scanning LUNS (drivers/scsi/scsi_scan.c in function __scsi_scan_target()): /* * Scan LUN 0, if there is some response, scan further. Ideally, we * would not configure LUN 0 until all LUNs are scanned. */ res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { if (scsi_report_lun_scan(starget, bflags, rescan) != 0) So, if we don't get a response while scanning LUN0, we will not use scsi_report_lun_scan(). On Hyper-V, the scsi emulation on the host does not treat LUN0 as anything special and we could have situations where the only device under a scsi controller is at a location other than 0 or 1. In this case the standard LUN scanning code in Linux fails to detect this device. Is this behaviour expected? Why is LUN0 treated differently here. Looking at the scsi spec, I am not sure if this is what is specified. Any help/guidance will be greatly appreciated. Regards, K. Y -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html