I'm crafting up a shell script (to be called by cron) that runs smartctl on the booted disk on a weekly basis. Is there a fairly universal way to determine what the boot block device is (IE - /dev/sda, /dev/hdb, etc)? The expected install would be standard, I think I could get away with using grep " / " on /etc/fstab, I'm just wondering if there's a more graceful way.
This script will specifically be deployed on Fedora and possibly Ubuntu boxes.
df -P / | tail -n 1 | awk '/.*/ { print $1 }'
Will return the root FS block device. Not necessarily the boot device though.
Better question might be why you're not scanning SMART on all the disks in the server?
for /boot:
readlink -f /dev/block/$(mountpoint -d /boot)
for rootfs:
readlink -f /dev/block/$(mountpoint -d /)
Explanation: 1) mountpoint -d - gives major:minor numbers of device mounted at
2) /dev/block folder - contains symlinks os all block devices by device numbers pointing back to regular device file in /dev
3) readlink -f - reconstruct device name from sym link
Works on all modern Linuxes
cat /proc/mounts |grep /boot |awk '{print $1}'
Will return something like /dev/sda1 if your /boot is not on the root device.
Combine this with the answer from Chris S.
You've probably long since moved on from this task, but I was trying to do something similar and figured I'd look into the missing piece of your puzzle, namely to get the drive designation (e.g. /dev/sda) instead of the partition designation (e.g. /dev/sda1).
I started off with Chris S's excellent answer (which also solved the task I was seeking to accomplish), and then just used good old fashioned bash string manipulation to trim the number off the end (leaving you with the drive vs the partition):
# first, save the output (e.g. /dev/sda1) to a variable
rootpart=$(df -P / | tail -n 1 | awk '/.*/ { print $1 }')
# now you can trim the number off:
echo ${rootpart//[[:digit:]]/}
# if ${rootpart} was "/dev/sda1", output would be "/dev/sda"
