Well, unmounting a read-only filesystem may very well go through without any SCSI request...
Anyway. Maybe the WD My Book does not handle the SCSI START STOP UNIT command like the Linux SCSI core expects. You could try adding a device quirks workaround which influences the parameters for this SCSI command. You can activate this workaround ad hoc by # modprobe sbp2 # echo 0x20 > /sys/module/sbp2/parameters/workarounds Then plug the disk in. You can enable this workaround permanently, i.e. persistent after any reboots and startups, by # echo "options sbp2 workarounds=0x20" >> /etc/modprobe.d/options But another reason could be that the WD My Book returns wrong SCSI status if it gets commands while in standby, leading the kernel's SCSI core to believe that all was fine and it hadn't to send START STOP UNIT at all. Then I don't see what could be done about it. -- WD My Book doesn't properly unmount on PC shutdown https://bugs.launchpad.net/bugs/311771 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs