udev: same serial on different disks

[Ervin Hegedüs <airween@gmail.com>]

Hello,

there is a Debian Etch with kernel 2.6.24-etchnhalf.1-686,
and udev 0.105.

System has two USB SATA-II disks for backup. Since a few weeks
the system can't make different between disks, all disks has
same serial.

# udevinfo -a -p /sys/block/sdb | grep serial
    ATTRS{serial}=="31AF4D71B008"
    ATTRS{serial}=="0000:00:1d.7"
# udevinfo -a -p /sys/block/sdc | grep serial
    ATTRS{serial}=="31AF4D71B008"
    ATTRS{serial}=="0000:00:1d.7"

# cat /dev/.udev/db/block\@sd[bc]
N:sdb
S:disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B008
S:disk/by-path/pci-0000:00:1d.7-usb-0:4:1.0-scsi-0:0:0:0
M:8:16
E:ID_VENDOR=SAMSUNG
E:ID_MODEL=HD642JJ
E:ID_REVISION=1112
E:ID_SERIAL=SAMSUNG_HD642JJ_31AF4D71B008
E:ID_TYPE=disk
E:ID_BUS=usb
E:ID_PATH=pci-0000:00:1d.7-usb-0:4:1.0-scsi-0:0:0:0
N:sdc
S:disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B008
S:disk/by-path/pci-0000:00:1d.7-usb-0:1:1.0-scsi-0:0:0:0
M:8:32
E:ID_VENDOR=SAMSUNG
E:ID_MODEL=HD642JJ
E:ID_REVISION=1112
E:ID_SERIAL=SAMSUNG_HD642JJ_31AF4D71B008
E:ID_TYPE=disk
E:ID_BUS=usb
E:ID_PATH=pci-0000:00:1d.7-usb-0:1:1.0-scsi-0:0:0:0

I would like to use two rules to identify disks when user
attach one of them, but system doesn't sense which disk
has attached.

The disk-by-id symlinks has created correctly:
# ls -l /dev/disk/by-id/usb*
lrwxrwxrwx 1 root root  9 2010-03-12 21:40
/dev/disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B000 -> ../../sdb
lrwxrwxrwx 1 root root 10 2010-03-12 21:40
/dev/disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B000-part1 -> ../../sdb1
lrwxrwxrwx 1 root root  9 2010-03-12 21:46
/dev/disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B008 -> ../../sdc
lrwxrwxrwx 1 root root 10 2010-03-12 21:46
/dev/disk/by-id/usb-SAMSUNG_HD642JJ_31AF4D71B008-part1 -> ../../sdc1

As you can see there are the correct serial numbers.

What could be the problem?


Thank you:

a.