Monitor mdadm array on desktop PC

monitor-mdadm.sh

#!/bin/bash

set -e
set -u

declare -r ARRAY_DEV="${1-}"
if [[ -z "$ARRAY_DEV" ]] ; then
  zenity --info --text "Usage: $0 [array_device]"
  exit -1
fi

declare -r array_status_file="/sys/block/$ARRAY_DEV/md/degraded"
if [[ ! -e "$array_status_file" ]] ; then
  zenity --info --text "Device does not exist? $ARRAY_DEV"
  exit -1
fi

array_status="$(cat /sys/block/$ARRAY_DEV/md/degraded)"
array_state="$(cat /sys/block/$ARRAY_DEV/md/array_state)"
logger -t 'monitor-mdadm' "Array $ARRAY_DEV is in state: $array_state (Degraded status: $array_status)"
if [[ "$array_status" -ne '0' ]] ; then
  zenity --warning --text "Array $ARRAY_DEV is degraded: $array_state"
fi

exit $array_status