何らかの理由でHDD接続が失われた場合は、udevルールを使用してRaspberry Pi（Debian Jessieを実行）がPushbulletにプッシュ通知を送信するようにします。今私はこれをうまくやりました。ただし、問題は、スクリプトが1回ではなく14回実行され、切断と接続操作で実行されることです。これは私の意図ではありません。
次のようにさまざまなルールファイルを設定しようとしました。
ACTION==”remove”,
KERNEL==”sda1”,
SUBSYSTEM==”block”,
KERNELS==”1-1.2”,
SUBSYSTEMS==”usb”,
ATTRS{idProduct}==”10a2”,
ATTRS{idVendor}==”1058”,
ATTRS{manufacturer}=="Western Digital",
RUN+="/home/pi/HDD_removed.sh"
そして
ACTION=="remove",
ENV{ID_MODEL}=="Elements_10A2",
RUN+="/home/pi/HDD_removed.sh"
そして他のものは何もうまくいきません..
助けるために、以下のudevadm infoとudevadm Monitorの出力を印刷しました（サイズが小さくて申し訳ありません...）。
$udevadm 情報 -a -p $(udevadm 情報 -q パス -n /dev/sda1)
looking at device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1':
KERNEL=="sda1"
SUBSYSTEM=="block"
DRIVER==""
ATTR{start}=="2048"
ATTR{inflight}==" 0 0"
ATTR{ro}=="0"
ATTR{partition}=="1"
ATTR{stat}==" 545 0 61544 4110 0 0 0 0 0 1320 4110"
ATTR{size}=="1953456128"
ATTR{alignment_offset}=="0"
ATTR{discard_alignment}=="0"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda':
KERNELS=="sda"
SUBSYSTEMS=="block"
DRIVERS==""
ATTRS{badblocks}==""
ATTRS{range}=="16"
ATTRS{capability}=="50"
ATTRS{inflight}==" 0 0"
ATTRS{ext_range}=="256"
ATTRS{ro}=="0"
ATTRS{stat}==" 590 0 62336 4140 0 0 0 0 0 1350 4140"
ATTRS{events_poll_msecs}=="-1"
ATTRS{events_async}==""
ATTRS{removable}=="0"
ATTRS{size}=="1953458176"
ATTRS{events}==""
ATTRS{alignment_offset}=="0"
ATTRS{discard_alignment}=="0"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0':
KERNELS=="0:0:0:0"
SUBSYSTEMS=="scsi"
DRIVERS=="sd"
ATTRS{evt_soft_threshold_reached}=="0"
ATTRS{evt_mode_parameter_change_reported}=="0"
ATTRS{inquiry}==""
ATTRS{evt_capacity_change_reported}=="0"
ATTRS{vendor}=="WD "
ATTRS{timeout}=="30"
ATTRS{evt_lun_change_reported}=="0"
ATTRS{evt_media_change}=="0"
ATTRS{queue_type}=="none"
ATTRS{device_busy}=="0"
ATTRS{eh_timeout}=="10"
ATTRS{model}=="Elements 10A2 "
ATTRS{iocounterbits}=="32"
ATTRS{queue_depth}=="1"
ATTRS{type}=="0"
ATTRS{evt_inquiry_change_reported}=="0"
ATTRS{max_sectors}=="240"
ATTRS{iodone_cnt}=="0x27d"
ATTRS{state}=="running"
ATTRS{iorequest_cnt}=="0x27d"
ATTRS{rev}=="1033"
ATTRS{ioerr_cnt}=="0x3"
ATTRS{scsi_level}=="7"
ATTRS{device_blocked}=="0"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0':
KERNELS=="target0:0:0"
SUBSYSTEMS=="scsi"
DRIVERS==""
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0':
KERNELS=="host0"
SUBSYSTEMS=="scsi"
DRIVERS==""
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0':
KERNELS=="1-1.2:1.0"
SUBSYSTEMS=="usb"
DRIVERS=="usb-storage"
ATTRS{bInterfaceProtocol}=="50"
ATTRS{bInterfaceNumber}=="00"
ATTRS{bInterfaceSubClass}=="06"
ATTRS{bInterfaceClass}=="08"
ATTRS{bAlternateSetting}==" 0"
ATTRS{authorized}=="1"
ATTRS{bNumEndpoints}=="02"
ATTRS{supports_autosuspend}=="1"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2':
KERNELS=="1-1.2"
SUBSYSTEMS=="usb"
DRIVERS=="usb"
ATTRS{bDeviceClass}=="00"
ATTRS{manufacturer}=="Western Digital"
ATTRS{bmAttributes}=="80"
ATTRS{bConfigurationValue}=="1"
ATTRS{version}==" 2.10"
ATTRS{devnum}=="9"
ATTRS{bMaxPower}=="100mA"
ATTRS{idProduct}=="10a2"
ATTRS{avoid_reset_quirk}=="0"
ATTRS{urbnum}=="7168"
ATTRS{bDeviceSubClass}=="00"
ATTRS{maxchild}=="0"
ATTRS{bcdDevice}=="1033"
ATTRS{bMaxPacketSize0}=="64"
ATTRS{idVendor}=="1058"
ATTRS{product}=="Elements 10A2"
ATTRS{speed}=="480"
ATTRS{removable}=="removable"
ATTRS{ltm_capable}=="no"
ATTRS{serial}=="575831314541323038393032"
ATTRS{bNumConfigurations}=="1"
ATTRS{busnum}=="1"
ATTRS{authorized}=="1"
ATTRS{quirks}=="0x0"
ATTRS{configuration}==""
ATTRS{devpath}=="1.2"
ATTRS{bDeviceProtocol}=="00"
ATTRS{bNumInterfaces}==" 1"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1/1-1':
KERNELS=="1-1"
SUBSYSTEMS=="usb"
DRIVERS=="usb"
ATTRS{bDeviceClass}=="09"
ATTRS{bmAttributes}=="e0"
ATTRS{bConfigurationValue}=="1"
ATTRS{version}==" 2.00"
ATTRS{devnum}=="2"
ATTRS{bMaxPower}=="2mA"
ATTRS{idProduct}=="9514"
ATTRS{avoid_reset_quirk}=="0"
ATTRS{urbnum}=="144"
ATTRS{bDeviceSubClass}=="00"
ATTRS{maxchild}=="5"
ATTRS{bcdDevice}=="0200"
ATTRS{bMaxPacketSize0}=="64"
ATTRS{idVendor}=="0424"
ATTRS{speed}=="480"
ATTRS{removable}=="unknown"
ATTRS{ltm_capable}=="no"
ATTRS{bNumConfigurations}=="1"
ATTRS{busnum}=="1"
ATTRS{authorized}=="1"
ATTRS{quirks}=="0x0"
ATTRS{configuration}==""
ATTRS{devpath}=="1"
ATTRS{bDeviceProtocol}=="02"
ATTRS{bNumInterfaces}==" 1"
looking at parent device '/devices/platform/soc/3f980000.usb/usb1':
KERNELS=="usb1"
SUBSYSTEMS=="usb"
DRIVERS=="usb"
ATTRS{bDeviceClass}=="09"
ATTRS{manufacturer}=="Linux 4.9.24-v7+ dwc_otg_hcd"
ATTRS{bmAttributes}=="e0"
ATTRS{bConfigurationValue}=="1"
ATTRS{version}==" 2.00"
ATTRS{devnum}=="1"
ATTRS{bMaxPower}=="0mA"
ATTRS{idProduct}=="0002"
ATTRS{avoid_reset_quirk}=="0"
ATTRS{urbnum}=="25"
ATTRS{bDeviceSubClass}=="00"
ATTRS{maxchild}=="1"
ATTRS{bcdDevice}=="0409"
ATTRS{bMaxPacketSize0}=="64"
ATTRS{idVendor}=="1d6b"
ATTRS{product}=="DWC OTG Controller"
ATTRS{speed}=="480"
ATTRS{authorized_default}=="1"
ATTRS{interface_authorized_default}=="1"
ATTRS{removable}=="unknown"
ATTRS{ltm_capable}=="no"
ATTRS{serial}=="3f980000.usb"
ATTRS{bNumConfigurations}=="1"
ATTRS{busnum}=="1"
ATTRS{authorized}=="1"
ATTRS{quirks}=="0x0"
ATTRS{configuration}==""
ATTRS{devpath}=="0"
ATTRS{bDeviceProtocol}=="01"
ATTRS{bNumInterfaces}==" 1"
looking at parent device '/devices/platform/soc/3f980000.usb':
KERNELS=="3f980000.usb"
SUBSYSTEMS=="platform"
DRIVERS=="dwc_otg"
ATTRS{wr_reg_test}=="Time to write GNPTXFSIZ reg 10000000 times: 540 msecs (54 jiffies)"
ATTRS{grxfsiz}=="GRXFSIZ = 0x00000306"
ATTRS{srpcapable}=="SRPCapable = 0x1"
ATTRS{buspower}=="Bus Power = 0x1"
ATTRS{bussuspend}=="Bus Suspend = 0x0"
ATTRS{hptxfsiz}=="HPTXFSIZ = 0x02000406"
ATTRS{hnp}=="HstNegScs = 0x0"
ATTRS{mode}=="Mode = 0x1"
ATTRS{mode_ch_tim_en}=="Mode Change Ready Timer Enable = 0x0"
ATTRS{hsic_connect}=="HSIC Connect = 0x1"
ATTRS{gsnpsid}=="GSNPSID = 0x4f54280a"
ATTRS{driver_override}=="(null)"
ATTRS{hcd_frrem}=="HCD Dump Frame Remaining"
ATTRS{gotgctl}=="GOTGCTL = 0x001c0001"
ATTRS{gpvndctl}=="GPVNDCTL = 0x00000000"
ATTRS{hnpcapable}=="HNPCapable = 0x1"
ATTRS{spramdump}=="SPRAM Dump"
ATTRS{regoffset}=="0xffffffff"
ATTRS{gnptxfsiz}=="GNPTXFSIZ = 0x01000306"
ATTRS{guid}=="GUID = 0x2708a000"
ATTRS{regdump}=="Register Dump"
ATTRS{hprt0}=="HPRT0 = 0x00001405"
ATTRS{hcddump}=="HCD Dump"
ATTRS{rem_wakeup_pwrdn}==""
ATTRS{regvalue}=="invalid offset"
ATTRS{gusbcfg}=="GUSBCFG = 0x20001700"
ATTRS{fr_interval}=="Frame Interval = 0x1d4b"
ATTRS{busconnected}=="Bus Connected = 0x1"
ATTRS{remote_wakeup}=="Remote Wakeup Sig = 0 Enabled = 0 LPM Remote Wakeup = 0"
ATTRS{devspeed}=="Device Speed = 0x0"
ATTRS{rd_reg_test}=="Time to read GNPTXFSIZ reg 10000000 times: 1500 msecs (150 jiffies)"
ATTRS{enumspeed}=="Device Enumeration Speed = 0x1"
ATTRS{inv_sel_hsic}=="Invert Select HSIC = 0x0"
ATTRS{ggpio}=="GGPIO = 0x00000000"
ATTRS{srp}=="SesReqScs = 0x1"
looking at parent device '/devices/platform/soc':
KERNELS=="soc"
SUBSYSTEMS=="platform"
DRIVERS==""
ATTRS{driver_override}=="(null)"
looking at parent device '/devices/platform':
KERNELS=="platform"
SUBSYSTEMS==""
DRIVERS==""
$ udevadmモニター - プロパティ
KERNEL[50982.358011] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/bsg/0:0:0:0 (bsg)
ACTION=remove
DEVNAME=/dev/bsg/0:0:0:0
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/bsg/0:0:0:0
MAJOR=251
MINOR=0
SEQNUM=1095
SUBSYSTEM=bsg
KERNEL[50982.359131] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_generic/sg0 (scsi_generic)
ACTION=remove
DEVNAME=/dev/sg0
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_generic/sg0
MAJOR=21
MINOR=0
SEQNUM=1096
SUBSYSTEM=scsi_generic
KERNEL[50982.359731] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_device/0:0:0:0 (scsi_device)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_device/0:0:0:0
SEQNUM=1097
SUBSYSTEM=scsi_device
KERNEL[50982.361349] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_disk/0:0:0:0 (scsi_disk)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_disk/0:0:0:0
SEQNUM=1098
SUBSYSTEM=scsi_disk
KERNEL[50982.367606] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1 (block)
ACTION=remove
DEVNAME=/dev/sda1
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1
DEVTYPE=partition
MAJOR=8
MINOR=1
PARTN=1
SEQNUM=1099
SUBSYSTEM=block
KERNEL[50982.369279] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda (block)
ACTION=remove
DEVNAME=/dev/sda
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda
DEVTYPE=disk
MAJOR=8
MINOR=0
SEQNUM=1100
SUBSYSTEM=block
KERNEL[50982.370139] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0
DEVTYPE=scsi_device
MODALIAS=scsi:t-0x00
SEQNUM=1101
SUBSYSTEM=scsi
KERNEL[50982.410910] remove /devices/virtual/bdi/8:0 (bdi)
ACTION=remove
DEVPATH=/devices/virtual/bdi/8:0
SEQNUM=1102
SUBSYSTEM=bdi
KERNEL[50982.411476] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0
DEVTYPE=scsi_target
SEQNUM=1103
SUBSYSTEM=scsi
KERNEL[50982.412387] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/scsi_host/host0 (scsi_host)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/scsi_host/host0
SEQNUM=1104
SUBSYSTEM=scsi_host
KERNEL[50982.414188] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0
DEVTYPE=scsi_host
SEQNUM=1105
SUBSYSTEM=scsi
KERNEL[50982.415487] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0 (usb)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0
DEVTYPE=usb_interface
INTERFACE=8/6/80
MODALIAS=usb:v1058p10A2d1033dc00dsc00dp00ic08isc06ip50in00
PRODUCT=1058/10a2/1033
SEQNUM=1106
SUBSYSTEM=usb
TYPE=0/0/0
KERNEL[50982.419788] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2 (usb)
ACTION=remove
BUSNUM=001
DEVNAME=/dev/bus/usb/001/007
DEVNUM=007
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2
DEVTYPE=usb_device
MAJOR=189
MINOR=6
PRODUCT=1058/10a2/1033
SEQNUM=1107
SUBSYSTEM=usb
TYPE=0/0/0
UDEV [50982.973557] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/bsg/0:0:0:0 (bsg)
ACTION=remove
DEVNAME=/dev/bsg/0:0:0:0
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/bsg/0:0:0:0
MAJOR=251
MINOR=0
SEQNUM=1095
SUBSYSTEM=bsg
USEC_INITIALIZED=982359004
UDEV [50982.999940] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_device/0:0:0:0 (scsi_device)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_device/0:0:0:0
SEQNUM=1097
SUBSYSTEM=scsi_device
USEC_INITIALIZED=982362751
UDEV [50983.095057] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1 (block)
ACTION=remove
DEVLINKS=/dev/disk/by-id/usb-WD_Elements_10A2_575831314541323038393032-0:0-part1 /dev/disk/by-label/Steven /dev/disk/by-path/platform-3f980000.usb-usb-0:1.2:1.0-scsi-0:0:0:0-part1 /dev/disk/by-uuid/21741F4F6C4915E1
DEVNAME=/dev/sda1
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1
DEVTYPE=partition
ID_BUS=usb
ID_FS_LABEL=Steven
ID_FS_LABEL_ENC=Steven
ID_FS_TYPE=ntfs
ID_FS_USAGE=filesystem
ID_FS_UUID=21741F4F6C4915E1
ID_FS_UUID_ENC=21741F4F6C4915E1
ID_INSTANCE=0:0
ID_MODEL=Elements_10A2
ID_MODEL_ENC=Elements\x2010A2\x20\x20\x20
ID_MODEL_ID=10a2
ID_PART_ENTRY_DISK=8:0
ID_PART_ENTRY_NUMBER=1
ID_PART_ENTRY_OFFSET=2048
ID_PART_ENTRY_SCHEME=dos
ID_PART_ENTRY_SIZE=1953456128
ID_PART_ENTRY_TYPE=0x7
ID_PART_ENTRY_UUID=00023f15-01
ID_PART_TABLE_TYPE=dos
ID_PART_TABLE_UUID=00023f15
ID_PATH=platform-3f980000.usb-usb-0:1.2:1.0-scsi-0:0:0:0
ID_PATH_TAG=platform-3f980000_usb-usb-0_1_2_1_0-scsi-0_0_0_0
ID_REVISION=1033
ID_SERIAL=WD_Elements_10A2_575831314541323038393032-0:0
ID_SERIAL_SHORT=575831314541323038393032
ID_TYPE=disk
ID_USB_DRIVER=usb-storage
ID_USB_INTERFACES=:080650:
ID_USB_INTERFACE_NUM=00
ID_VENDOR=WD
ID_VENDOR_ENC=WD\x20\x20\x20\x20\x20\x20
ID_VENDOR_ID=1058
MAJOR=8
MINOR=1
PARTN=1
SEQNUM=1099
SUBSYSTEM=block
TAGS=:systemd:
USEC_INITIALIZED=8036767
UDEV [50983.126799] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_disk/0:0:0:0 (scsi_disk)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_disk/0:0:0:0
SEQNUM=1098
SUBSYSTEM=scsi_disk
USEC_INITIALIZED=982364537
UDEV [50983.136895] remove /devices/virtual/bdi/8:0 (bdi)
ACTION=remove
DEVPATH=/devices/virtual/bdi/8:0
SEQNUM=1102
SUBSYSTEM=bdi
USEC_INITIALIZED=982411342
UDEV [50983.138940] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_generic/sg0 (scsi_generic)
ACTION=remove
DEVNAME=/dev/sg0
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/scsi_generic/sg0
MAJOR=21
MINOR=0
SEQNUM=1096
SUBSYSTEM=scsi_generic
USEC_INITIALIZED=982360886
KERNEL[50983.194516] remove /devices/virtual/bdi/8:1-fuseblk (bdi)
ACTION=remove
DEVPATH=/devices/virtual/bdi/8:1-fuseblk
SEQNUM=1108
SUBSYSTEM=bdi
UDEV [50983.204265] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/scsi_host/host0 (scsi_host)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/scsi_host/host0
SEQNUM=1104
SUBSYSTEM=scsi_host
USEC_INITIALIZED=982413320
UDEV [50983.643690] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda (block)
ACTION=remove
DEVLINKS=/dev/disk/by-id/usb-WD_Elements_10A2_575831314541323038393032-0:0 /dev/disk/by-path/platform-3f980000.usb-usb-0:1.2:1.0-scsi-0:0:0:0
DEVNAME=/dev/sda
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0/block/sda
DEVTYPE=disk
ID_BUS=usb
ID_INSTANCE=0:0
ID_MODEL=Elements_10A2
ID_MODEL_ENC=Elements\x2010A2\x20\x20\x20
ID_MODEL_ID=10a2
ID_PART_TABLE_TYPE=dos
ID_PART_TABLE_UUID=00023f15
ID_PATH=platform-3f980000.usb-usb-0:1.2:1.0-scsi-0:0:0:0
ID_PATH_TAG=platform-3f980000_usb-usb-0_1_2_1_0-scsi-0_0_0_0
ID_REVISION=1033
ID_SERIAL=WD_Elements_10A2_575831314541323038393032-0:0
ID_SERIAL_SHORT=575831314541323038393032
ID_TYPE=disk
ID_USB_DRIVER=usb-storage
ID_USB_INTERFACES=:080650:
ID_USB_INTERFACE_NUM=00
ID_VENDOR=WD
ID_VENDOR_ENC=WD\x20\x20\x20\x20\x20\x20
ID_VENDOR_ID=1058
MAJOR=8
MINOR=0
SEQNUM=1100
SUBSYSTEM=block
TAGS=:systemd:
USEC_INITIALIZED=748036370
UDEV [50983.733473] remove /devices/virtual/bdi/8:1-fuseblk (bdi)
ACTION=remove
DEVPATH=/devices/virtual/bdi/8:1-fuseblk
SEQNUM=1108
SUBSYSTEM=bdi
USEC_INITIALIZED=3192262
UDEV [50984.141379] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0/0:0:0:0
DEVTYPE=scsi_device
MODALIAS=scsi:t-0x00
SEQNUM=1101
SUBSYSTEM=scsi
USEC_INITIALIZED=2371212
UDEV [50984.629455] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0/target0:0:0
DEVTYPE=scsi_target
SEQNUM=1103
SUBSYSTEM=scsi
USEC_INITIALIZED=2413053
UDEV [50985.087418] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0 (scsi)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0/host0
DEVTYPE=scsi_host
SEQNUM=1105
SUBSYSTEM=scsi
USEC_INITIALIZED=2415484
UDEV [50985.618300] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0 (usb)
ACTION=remove
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.0
DEVTYPE=usb_interface
ID_MODEL_FROM_DATABASE=Elements SE Portable (WDBPCK)
ID_VENDOR_FROM_DATABASE=Western Digital Technologies, Inc.
INTERFACE=8/6/80
MODALIAS=usb:v1058p10A2d1033dc00dsc00dp00ic08isc06ip50in00
PRODUCT=1058/10a2/1033
SEQNUM=1106
SUBSYSTEM=usb
TYPE=0/0/0
USEC_INITIALIZED=5647475
UDEV [50986.078354] remove /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2 (usb)
ACTION=remove
BUSNUM=001
DEVNAME=/dev/bus/usb/001/007
DEVNUM=007
DEVPATH=/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2
DEVTYPE=usb_device
ID_BUS=usb
ID_MODEL=Elements_10A2
ID_MODEL_ENC=Elements\x2010A2
ID_MODEL_FROM_DATABASE=Elements SE Portable (WDBPCK)
ID_MODEL_ID=10a2
ID_REVISION=1033
ID_SERIAL=Western_Digital_Elements_10A2_575831314541323038393032
ID_SERIAL_SHORT=575831314541323038393032
ID_USB_INTERFACES=:080650:
ID_VENDOR=Western_Digital
ID_VENDOR_ENC=Western\x20Digital
ID_VENDOR_FROM_DATABASE=Western Digital Technologies, Inc.
ID_VENDOR_ID=1058
MAJOR=189
MINOR=6
PRODUCT=1058/10a2/1033
SEQNUM=1107
SUBSYSTEM=usb
TYPE=0/0/0
USEC_INITIALIZED=745644833
答え1
ありがとう12月解決策を見つけるには：
実際、ルールは1行にする必要があります。これにより、重複したスクリプト呼び出しが修正されました（固有の変数を使用している場合）。これで、デバイスが切断された場合にのみスクリプトが呼び出されます。私にとって、次の設定はトリックを実行しました。
ACTION=="remove", ENV{ID_FS_UUID}=="21741F4F6C4915E1", RUN+="/home/pi/HDD_removed.sh"
答え2
他の人がすでに指摘したように、コードスニペットの各行は何もしないか（orのみの行==）、すべてのudevイベントに対してコマンドを実行する（=orのみの行+=）、別々のルールです。ルール全体を1つの論理行に配置する必要があります。
udevルールで行を分割できますが、ルールが次の行に続く場合は、行の末尾にバックスラッシュを追加する必要があります。つまり、論理行にはバックスラッシュ - 改行文字の2文字のシーケンスを含めることができ、このシーケンスは無視されます。
ACTION=="remove", \
ENV{ID_MODEL}=="Elements_10A2", \
RUN+="/home/pi/HDD_removed.sh"