我出于测试目的编写了这条规则：
SUBSYSTEMS=="usb", ATTRS{manufacturer}=="Kingston", ATTRS{serial}=="001CC0EC34A2BB318709004B", ATTRS{idVendor}=="0951", ATTRS{idProduct}=="1642", SYMLINK+="pen", NAME="pendrak"
基于以下信息：
# udevadm info --name=/dev/sdb --attribute-walk
Udevadm info starts with the device specified by the devpath and then
walks up the chain of parent devices. It prints for every device
found, all possible attributes in the udev rules key format.
A rule to match, can be composed by the attributes of the device
and the attributes from one single parent device.
looking at device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb':
KERNEL=="sdb"
SUBSYSTEM=="block"
DRIVER==""
ATTR{ro}=="0"
ATTR{size}=="30299520"
ATTR{stat}==" 419 0 3352 1208 0 0 0 0 0 1120 1208"
ATTR{range}=="16"
ATTR{discard_alignment}=="0"
ATTR{events}=="media_change"
ATTR{ext_range}=="256"
ATTR{events_poll_msecs}=="3000"
ATTR{alignment_offset}=="0"
ATTR{inflight}==" 0 0"
ATTR{removable}=="1"
ATTR{capability}=="51"
ATTR{events_async}==""
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0':
KERNELS=="2:0:0:0"
SUBSYSTEMS=="scsi"
DRIVERS=="sd"
ATTRS{rev}=="PMAP"
ATTRS{type}=="0"
ATTRS{scsi_level}=="0"
ATTRS{model}=="DT 101 G2 "
ATTRS{state}=="running"
ATTRS{queue_type}=="none"
ATTRS{iodone_cnt}=="0x2da"
ATTRS{iorequest_cnt}=="0x2da"
ATTRS{evt_capacity_change_reported}=="0"
ATTRS{timeout}=="30"
ATTRS{evt_media_change}=="0"
ATTRS{max_sectors}=="240"
ATTRS{ioerr_cnt}=="0x2"
ATTRS{queue_depth}=="1"
ATTRS{vendor}=="Kingston"
ATTRS{evt_soft_threshold_reached}=="0"
ATTRS{device_blocked}=="0"
ATTRS{evt_mode_parameter_change_reported}=="0"
ATTRS{evt_lun_change_reported}=="0"
ATTRS{evt_inquiry_change_reported}=="0"
ATTRS{iocounterbits}=="32"
ATTRS{eh_timeout}=="10"
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0':
KERNELS=="target2:0:0"
SUBSYSTEMS=="scsi"
DRIVERS==""
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2':
KERNELS=="host2"
SUBSYSTEMS=="scsi"
DRIVERS==""
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0':
KERNELS=="2-5:1.0"
SUBSYSTEMS=="usb"
DRIVERS=="usb-storage"
ATTRS{bInterfaceClass}=="08"
ATTRS{bInterfaceSubClass}=="06"
ATTRS{bInterfaceProtocol}=="50"
ATTRS{bNumEndpoints}=="02"
ATTRS{supports_autosuspend}=="1"
ATTRS{bAlternateSetting}==" 0"
ATTRS{bInterfaceNumber}=="00"
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2/2-5':
KERNELS=="2-5"
SUBSYSTEMS=="usb"
DRIVERS=="usb"
ATTRS{bDeviceSubClass}=="00"
ATTRS{bDeviceProtocol}=="00"
ATTRS{devpath}=="5"
ATTRS{idVendor}=="0951"
ATTRS{speed}=="480"
ATTRS{bNumInterfaces}==" 1"
ATTRS{bConfigurationValue}=="1"
ATTRS{bMaxPacketSize0}=="64"
ATTRS{busnum}=="2"
ATTRS{devnum}=="4"
ATTRS{configuration}==""
ATTRS{bMaxPower}=="200mA"
ATTRS{authorized}=="1"
ATTRS{bmAttributes}=="80"
ATTRS{bNumConfigurations}=="1"
ATTRS{maxchild}=="0"
ATTRS{bcdDevice}=="0100"
ATTRS{avoid_reset_quirk}=="0"
ATTRS{quirks}=="0x0"
ATTRS{serial}=="001CC0EC34A2BB318709004B"
ATTRS{version}==" 2.00"
ATTRS{urbnum}=="1927"
ATTRS{ltm_capable}=="no"
ATTRS{manufacturer}=="Kingston"
ATTRS{removable}=="unknown"
ATTRS{idProduct}=="1642"
ATTRS{bDeviceClass}=="00"
ATTRS{product}=="DT 101 G2"
looking at parent device '/devices/pci0000:00/0000:00:1d.7/usb2':
KERNELS=="usb2"
SUBSYSTEMS=="usb"
DRIVERS=="usb"
ATTRS{bDeviceSubClass}=="00"
ATTRS{bDeviceProtocol}=="00"
ATTRS{devpath}=="0"
ATTRS{idVendor}=="1d6b"
ATTRS{speed}=="480"
ATTRS{bNumInterfaces}==" 1"
ATTRS{bConfigurationValue}=="1"
ATTRS{bMaxPacketSize0}=="64"
ATTRS{authorized_default}=="1"
ATTRS{busnum}=="2"
ATTRS{devnum}=="1"
ATTRS{configuration}==""
ATTRS{bMaxPower}=="0mA"
ATTRS{authorized}=="1"
ATTRS{bmAttributes}=="e0"
ATTRS{bNumConfigurations}=="1"
ATTRS{maxchild}=="8"
ATTRS{bcdDevice}=="0312"
ATTRS{avoid_reset_quirk}=="0"
ATTRS{quirks}=="0x0"
ATTRS{serial}=="0000:00:1d.7"
ATTRS{version}==" 2.00"
ATTRS{urbnum}=="89"
ATTRS{ltm_capable}=="no"
ATTRS{manufacturer}=="Linux 3.12-1-amd64 ehci_hcd"
ATTRS{removable}=="unknown"
ATTRS{idProduct}=="0002"
ATTRS{bDeviceClass}=="09"
ATTRS{product}=="EHCI Host Controller"
looking at parent device '/devices/pci0000:00/0000:00:1d.7':
KERNELS=="0000:00:1d.7"
SUBSYSTEMS=="pci"
DRIVERS=="ehci-pci"
ATTRS{irq}=="23"
ATTRS{subsystem_vendor}=="0x1458"
ATTRS{broken_parity_status}=="0"
ATTRS{class}=="0x0c0320"
ATTRS{companion}==""
ATTRS{consistent_dma_mask_bits}=="32"
ATTRS{dma_mask_bits}=="32"
ATTRS{local_cpus}=="00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000003"
ATTRS{device}=="0x27cc"
ATTRS{uframe_periodic_max}=="100"
ATTRS{enable}=="1"
ATTRS{msi_bus}==""
ATTRS{local_cpulist}=="0-1"
ATTRS{vendor}=="0x8086"
ATTRS{subsystem_device}=="0x5006"
ATTRS{numa_node}=="-1"
ATTRS{d3cold_allowed}=="1"
looking at parent device '/devices/pci0000:00':
KERNELS=="pci0000:00"
SUBSYSTEMS==""
DRIVERS==""
和：
# udevadm info --name=/dev/sdb
P: /devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
N: sdb
S: disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
S: disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
S: pen
E: DEVLINKS=/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0 /dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0 /dev/pen
E: DEVNAME=/dev/sdb
E: DEVPATH=/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
E: DEVTYPE=disk
E: ID_BUS=usb
E: ID_INSTANCE=0:0
E: ID_MODEL=DT_101_G2
E: ID_MODEL_ENC=DT\x20101\x20G2\x20\x20\x20\x20\x20\x20\x20
E: ID_MODEL_ID=1642
E: ID_PART_TABLE_TYPE=dos
E: ID_PATH=pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
E: ID_PATH_TAG=pci-0000_00_1d_7-usb-0_5_1_0-scsi-0_0_0_0
E: ID_REVISION=PMAP
E: ID_SERIAL=Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
E: ID_SERIAL_SHORT=001CC0EC34A2BB318709004B
E: ID_TYPE=disk
E: ID_USB_DRIVER=usb-storage
E: ID_USB_INTERFACES=:080650:
E: ID_USB_INTERFACE_NUM=00
E: ID_VENDOR=Kingston
E: ID_VENDOR_ENC=Kingston
E: ID_VENDOR_ID=0951
E: MAJOR=8
E: MINOR=16
E: SUBSYSTEM=block
E: USEC_INITIALIZED=32380484
但是当我想测试它时，它给了我这个日志：
# udevadm test /devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
calling: test
version 204
This program is for debugging only, it does not run any program
specified by a RUN key. It may show incorrect results, because
some values may be different, or not available at a simulation run.
=== trie on-disk ===
tool version: 204
file size: 5729797 bytes
header size 80 bytes
strings 1262125 bytes
nodes 4467592 bytes
load module index
Skipping overridden file: /lib/udev/rules.d/95-keymap.rules.
read rules file: /lib/udev/rules.d/42-usb-hid-pm.rules
read rules file: /lib/udev/rules.d/50-firmware.rules
read rules file: /lib/udev/rules.d/50-udev-default.rules
read rules file: /lib/udev/rules.d/55-dm.rules
read rules file: /lib/udev/rules.d/56-lvm.rules
read rules file: /lib/udev/rules.d/60-cdrom_id.rules
read rules file: /lib/udev/rules.d/60-fuse.rules
read rules file: /lib/udev/rules.d/60-gnupg.rules
read rules file: /lib/udev/rules.d/60-libfreenect0.2.rules
read rules file: /lib/udev/rules.d/60-libgphoto2-6.rules
read rules file: /lib/udev/rules.d/60-libpisock9.rules
read rules file: /lib/udev/rules.d/60-libsane.rules
read rules file: /lib/udev/rules.d/60-nvidia-kernel-common.rules
read rules file: /lib/udev/rules.d/60-pcmcia.rules
read rules file: /lib/udev/rules.d/60-persistent-alsa.rules
read rules file: /lib/udev/rules.d/60-persistent-input.rules
read rules file: /lib/udev/rules.d/60-persistent-serial.rules
read rules file: /lib/udev/rules.d/60-persistent-storage-dm.rules
read rules file: /lib/udev/rules.d/60-persistent-storage-tape.rules
read rules file: /lib/udev/rules.d/60-persistent-storage.rules
read rules file: /lib/udev/rules.d/60-persistent-v4l.rules
read rules file: /lib/udev/rules.d/60-virtualbox-dkms.rules
read rules file: /lib/udev/rules.d/60-virtualbox.rules
read rules file: /lib/udev/rules.d/61-accelerometer.rules
read rules file: /etc/udev/rules.d/61-removable-storage-polling.rules
read rules file: /lib/udev/rules.d/64-btrfs.rules
read rules file: /lib/udev/rules.d/64-xorg-xkb.rules
read rules file: /lib/udev/rules.d/69-cd-sensors.rules
IMPORT found builtin 'usb_id --export %p', replacing /lib/udev/rules.d/69-cd-sensors.rules:89
read rules file: /lib/udev/rules.d/69-libmtp.rules
read rules file: /lib/udev/rules.d/69-lvm-metad.rules
read rules file: /lib/udev/rules.d/69-xorg-vmmouse.rules
read rules file: /lib/udev/rules.d/70-btrfs.rules
read rules file: /etc/udev/rules.d/70-persistent-cd.rules
read rules file: /etc/udev/rules.d/70-persistent-net.rules
read rules file: /lib/udev/rules.d/70-power-switch.rules
read rules file: /lib/udev/rules.d/70-udev-acl.rules
read rules file: /etc/udev/rules.d/70-zram.rules
read rules file: /lib/udev/rules.d/75-cd-aliases-generator.rules
read rules file: /lib/udev/rules.d/75-net-description.rules
read rules file: /lib/udev/rules.d/75-persistent-net-generator.rules
read rules file: /lib/udev/rules.d/75-probe_mtd.rules
read rules file: /lib/udev/rules.d/75-tty-description.rules
read rules file: /lib/udev/rules.d/78-sound-card.rules
read rules file: /lib/udev/rules.d/80-btrfs-lvm.rules
read rules file: /lib/udev/rules.d/80-drivers.rules
read rules file: /lib/udev/rules.d/80-net-name-slot.rules
read rules file: /lib/udev/rules.d/80-networking.rules
read rules file: /lib/udev/rules.d/85-hdparm.rules
read rules file: /lib/udev/rules.d/85-hwclock.rules
read rules file: /lib/udev/rules.d/90-alsa-restore.rules
read rules file: /lib/udev/rules.d/90-pulseaudio.rules
read rules file: /lib/udev/rules.d/91-permissions.rules
read rules file: /lib/udev/rules.d/95-cd-devices.rules
read rules file: /lib/udev/rules.d/95-keyboard-force-release.rules
read rules file: /etc/udev/rules.d/95-keymap.rules
read rules file: /lib/udev/rules.d/95-udev-late.rules
read rules file: /lib/udev/rules.d/97-bluetooth-hid2hci.rules
read rules file: /etc/udev/rules.d/99-local.rules
rules contain 393216 bytes tokens (32768 * 12 bytes), 31233 bytes strings
27768 strings (226512 bytes), 24687 de-duplicated (198361 bytes), 3082 trie nodes used
IMPORT builtin 'usb_id' /lib/udev/rules.d/60-persistent-storage.rules:68
/sys/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0: if_class 8 protocol 6
IMPORT builtin 'path_id' /lib/udev/rules.d/60-persistent-storage.rules:89
LINK 'disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' /lib/udev/rules.d/60-persistent-storage.rules:108
LINK 'disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' /lib/udev/rules.d/60-persistent-storage.rules:130
IMPORT '/sbin/blkid -o udev -p /dev/sdb' /lib/udev/rules.d/60-persistent-storage.rules:151
starting '/sbin/blkid -o udev -p /dev/sdb'
'/sbin/blkid -o udev -p /dev/sdb' [12103] exit with return code 0
RUN '/etc/init.d/hdparm hotplug' /lib/udev/rules.d/85-hdparm.rules:1
GROUP 6 /lib/udev/rules.d/91-permissions.rules:4
GROUP 25 /lib/udev/rules.d/91-permissions.rules:5
GROUP 25 /lib/udev/rules.d/91-permissions.rules:9
NAME="pendrak" ignored, kernel device nodes can not be renamed; please fix it in /etc/udev/rules.d/99-local.rules:1
LINK 'pen' /etc/udev/rules.d/99-local.rules:1
handling device node '/dev/sdb', devnum=b8:16, mode=0660, uid=0, gid=25
preserve permissions /dev/sdb, 060660, uid=0, gid=25
preserve already existing symlink '/dev/block/8:16' to '../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fdisk\x2fby-id\x2fusb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0'
creating link '/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' to '/dev/sdb'
preserve already existing symlink '/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0' to '../../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fdisk\x2fby-path\x2fpci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0'
creating link '/dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' to '/dev/sdb'
preserve already existing symlink '/dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0' to '../../sdb'
found 'b8:16' claiming '/run/udev/links/\x2fpen'
creating link '/dev/pen' to '/dev/sdb'
preserve already existing symlink '/dev/pen' to 'sdb'
.ID_FS_TYPE_NEW=
ACTION=add
DEVLINKS=/dev/disk/by-id/usb-Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0 /dev/disk/by-path/pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0 /dev/pen
DEVNAME=/dev/sdb
DEVPATH=/devices/pci0000:00/0000:00:1d.7/usb2/2-5/2-5:1.0/host2/target2:0:0/2:0:0:0/block/sdb
DEVTYPE=disk
ID_BUS=usb
ID_FS_TYPE=
ID_INSTANCE=0:0
ID_MODEL=DT_101_G2
ID_MODEL_ENC=DT\x20101\x20G2\x20\x20\x20\x20\x20\x20\x20
ID_MODEL_ID=1642
ID_PART_TABLE_TYPE=dos
ID_PATH=pci-0000:00:1d.7-usb-0:5:1.0-scsi-0:0:0:0
ID_PATH_TAG=pci-0000_00_1d_7-usb-0_5_1_0-scsi-0_0_0_0
ID_REVISION=PMAP
ID_SERIAL=Kingston_DT_101_G2_001CC0EC34A2BB318709004B-0:0
ID_SERIAL_SHORT=001CC0EC34A2BB318709004B
ID_TYPE=disk
ID_USB_DRIVER=usb-storage
ID_USB_INTERFACES=:080650:
ID_USB_INTERFACE_NUM=00
ID_VENDOR=Kingston
ID_VENDOR_ENC=Kingston
ID_VENDOR_ID=0951
MAJOR=8
MINOR=16
SUBSYSTEM=block
USEC_INITIALIZED=32380484
run: '/etc/init.d/hdparm hotplug'
unload module index
正如您所看到的，符号链接已创建，但名称未更改，并且出现以下错误：
NAME="pendrak" ignored, kernel device nodes can not be renamed; please fix it in /etc/udev/rules.d/99-local.rules:1
另一件事是链接随机指向 sdb、sdb1、sdb2 等：
# ls -al /dev/pen
lrwxrwxrwx 1 root root 3 Mar 13 12:49 /dev/pen -> sdb
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb2
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb1
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb2
# ls -al /dev/pen
lrwxrwxrwx 1 root root 4 Mar 13 12:53 /dev/pen -> sdb3
每次我插入随身碟时它都会改变。
这里的任务是将设备的名称从 sdb （或其他任何名称）更改为pendrak并创建指向它的链接。该错误声称“内核设备节点无法重命名”——这是否意味着我根本无法更改名称，而我所能做的就是创建符号链接？
答案1
根据 udev 手册，无法更改/dev/目录中文件的名称：
NAME
The name to use for a network interface. The name of a device node
cannot be changed by udev, only additional symlinks can be created.
因此，就我而言，我应该编写类似于以下的规则：
KERNEL=="sd?3", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
SYMLINK+="pen%n", \
RUN+="/usr/bin/udevil mount /dev/pen%n /mnt/dane"
KERNEL=="sd?1", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
SYMLINK+="pen%n", \
RUN+="/usr/bin/udevil mount /dev/pen%n /mnt/debian"
KERNEL=="sd?2", ACTION=="add", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
SYMLINK+="pen%n", \
RUN+="/sbin/cryptsetup luksOpen /dev/pen%n pen%n --key-file=/home/morfik/Desktop/pen2.key", \
RUN+="/usr/bin/udevil mount /dev/mapper/pen%n /mnt/szyfr"
KERNEL=="sd?2", ACTION=="remove", ENV{ID_SERIAL_SHORT}=="001CC0EC34A2BB318709004B", \
RUN+="/sbin/cryptsetup luksClose pen%n"
他们创建三个链接：pen1、pen2、pen3。每个都链接到相应的 sdb（或任何可能的）设备，并且只需通过 udevil 工具打开并将它们安装到指定目录中。