Dead simple alerts when your mdadm array degrades without setting up a full blown MTA

chkraid.sh

#!/bin/bash

# dead simple mdadm alerts via webhook
# by eric barch [v1.0 -- 2018.11.26]


# 1. place this file in ~/chkraid.sh
#    chmod +x ~/chkraid.sh

# 2. drop this in your crontab:
#    0 * * * *       /home/<your_username>/chkraid.sh

# 3. get free account at http://healthchecks.io (no affiliation)
#    then create a new healh check (period: one hour) and paste the URL below
SUCCESS_URL_HEALTHCHECK="https://hc-ping.com/YOUR_CHECK_URL"

# 4. fill in the substring that represents your healthy array
#    helpful info on the output of /proc/mdstat here:
#    https://raid.wiki.kernel.org/index.php/Mdstat#md_config.2Fstatus_line

#    example: a dual RAID array (U represents a drive that is up)
RAID_HEALTHY_SUBSTRING="[UU]"

# 5. make sure you have curl installed


echo "Checking status of RAID array..."

raid_status=$(cat /proc/mdstat)

if [[ $raid_status == *"$RAID_HEALTHY_SUBSTRING"* ]]; then
    echo "It's good!"
    /usr/bin/curl $SUCCESS_URL_HEALTHCHECK
else
    echo "Ahhhhh!"
fi