How to automatically mount/unmount an external USB hard drive

85-external-drive-rule.rules

# File: /etc/udev/rules.d/85-external-drive-rule.rules

# Rules for auto-mounting/unmounting USB drives
ACTION=="add", ENV{ID_MODEL}=="USB_to_ATA_ATAPI_bridge", ENV{ID_VENDOR_ID}=="152d", ENV{ID_MODEL_ID}=="2338", RUN+="/usr/local/bin/automount.sh"
ACTION=="remove", ENV{ID_MODEL}=="USB_to_ATA_ATAPI_bridge", ENV{ID_VENDOR_ID}=="152d", ENV{ID_MODEL_ID}=="2338", RUN+="/usr/local/bin/unmount.sh"

# Notes:
# To detect your own drive's ID_MODEL, ID_MODEL_ID, and ID_VENDOR_ID, run "udevadm monitor --environment --udev" before plugging/unplugging the drive
# To force udev to reload these rules (without reboot), run "udevadm control --reload-rules" and "udevadm trigger"
# To change udev's logging level (written to /var/log/syslog), you can run "udevadm control --log-priority=info" (or debug), or configure it via /etc/udev/udev.conf

automount.sh

#!/bin/bash
# File: /usr/local/bin/automount.sh

# Wait a few seconds for the drive to spin up after connecting
sleep 5
# Use the rules in /etc/fstab to automatically mount the drive
/bin/mount -a

# Tell the drive to spin down after 10 minutes
if [ -e /dev/sda ]; then
  /sbin/hdparm -K1 -S120 /dev/sda
fi
if [ -e /dev/sdb ]; then
  /sbin/hdparm -K1 -S120 /dev/sdb
fi

fstab

# File: /etc/fstab

# OS partitions (don't mess with 'em):
proc            /proc           proc    defaults          0       0
/dev/mmcblk0p1  /boot           vfat    defaults          0       2
/dev/mmcblk0p2  /               ext4    defaults,noatime  0       1

# At boot-time, automatically mount your external HDD, if detected
# To find the UUID, run "blkid"
UUID=<partition-uuid>     /mnt/<path>      ntfs-3g     defaults,auto,noatime,nodiratime,noexec     0     0

unmount.sh

#!/bin/bash
# File: /usr/local/bin/unmount.sh

# The path you use could be the partition in /dev or could be the mount-point (something under /mnt, /media)
/bin/umount /mnt/<path>

~README.txt

A 3TB internal SATA drive is connected to my Raspberry Pi 2 Model B via a USB-to-SATA adapter.

I am using the RPi to run kodi; all the movies, videos, and TV shows are contained in the hard-drive.

My goals for drive-management are:
* To automatically detect and mount the drive at boot-time (if detected) => use /etc/fstab
* To automatically detect and mount the drive after boot-time (whenever hot-plugged) => write custom /etc/udev/rules.d/*.rules
* To automatically unmount the drive when it is unplugged/powered-off => write custom /etc/udev/rules.d/*.rules
* To spin down the hard-drive after a period of inactivity => piggy-back off the udev rules