redhat enterprise linux 4/ oracle linux 4下怎样用udev绑定块设备？

motes

如题。vbox下的oel4。
/etc/udev/rules.d/20-asmdisks.rules内容：
KERNEL="sd*", BUS="scsi", PROGRAM="/sbin/scsi_id -g -u -s %p", RESULT="1ATA_____VBOX_HARDDISK___________________________VB64c991c1-0f1e0687_", NAME="diskc", OWNER="oracle", GROUP="oinstall", MODE="0660"
KERNEL="sd*", BUS="scsi", PROGRAM="/sbin/scsi_id -g -u -s %p", RESULT="1ATA_____VBOX_HARDDISK___________________________VB1392a55e-fbae7647_", NAME="diskd", OWNER="oracle", GROUP="oinstall", MODE="0660"


#udevtest /block/sdc
version 039
looking at '/block/sdc'
Non block or class device '/sys'
Non block or class device '/sys'

我想把设备/dev/sdc和/dev/sdd通过Udev作永久命名绑定。不知道rules文件该怎样写？