Storage Hard Drives SSD
Hard Drives do not seem to do well crashing under Linux.
SSDs

Raspberry seems to go amuck just using SD cards.

Number of hard reboots as test... 20

USB Thumb Drives have given good results.



Raspberry Running on USB thumb Drive or other Mass Storage.
Raspberry III and newer.

sudo fdisk -l

sudo raspi-config

expand file system
Then df   
pi@raspbian-pi2 ~ $ df
Filesystem     1K-blocks    Used Available Use% Mounted on
rootfs          15190708 2658004  11871552  19% /
/dev/root       15190708 2658004  11871552  19% /



WD Scorpio Blue 750 GB Mobile Hard Drive:

Electrical Specifications
+5 VDC Current Requirements
Read/Write : 500 mA (2.5 Watts)
Idle : 400 mA (2.0 Watts)
Standby : 50 mA (0.25 Watts)
Sleep : 20 mA (0.1 Watts)