I have a similarly described problem to this question: http://superuser.com/questions/90181/same-scsi-drive-appears-multiple-times-on-the-controller-list where a SCSI direct-access device appears as multiple lun's, when it should only be one. The device is a SCSI-1 device, the SCSI controller card is an Adaptec AHA-7850 (rev 03), and system is PC / Linux 2.6. This device worked fine with RHEL4, and appeared as a single device / lun when the OS booted, but I've just tried plugging the device into a newer Linux disto (CentOS 5.4) and it now sees the device as 8 luns; with consequently 8 device files /dev/sgb to /dev/sgi. Any clues of how to figure out where the problem / fix is, would be great.