Turn off TrueNAS when system is idle

turn_off_on_idle.sh

#!/bin/bash

INACTIVE_THRESHOLD=1800  # 30 minutes in seconds
CHECK_INTERVAL=1  # How often to check disk activity, in seconds
SAMPLE_DURATION=1  # Duration for iostat to collect data, in seconds
DEBUG=1  # Set to 1 to enable debug mode, 0 to disable

LOW_ACTIVITY_THRESHOLD_READ=5000  # Threshold for read activity in kB/s, adjust as needed
LOW_ACTIVITY_THRESHOLD_WRITE=5000  # Threshold for write activity in kB/s, adjust as needed

last_activity_time=$(date +%s)

if [ "$DEBUG" -eq 1 ]; then
    echo "Starting disk activity monitoring in debug mode..."
else
    echo "Starting disk activity monitoring..."
fi

# List all disks excluding specific patterns (e.g., loop devices) and get only the name column
DISKS=$(lsblk -nd -o name | grep -v '^loop')

while true; do
    current_time=$(date +%s)
    low_activity_disks=0
    total_disks=0

    for DISK in $DISKS; do
        iostat_output=$(iostat -x ${DISK} ${SAMPLE_DURATION} 2)
        read_activity=$(echo "$iostat_output" | awk -v disk="$DISK" '$0 ~ disk {getline; print $3}')
        write_activity=$(echo "$iostat_output" | awk -v disk="$DISK" '$0 ~ disk {getline; print $9}')

        if [ "$DEBUG" -eq 1 ]; then
            echo "Disk: $DISK, Current Read activity: $read_activity kB/s, Current Write activity: $write_activity kB/s"
        fi

        read_active=$(awk -v ra="$read_activity" -v threshold="$LOW_ACTIVITY_THRESHOLD_READ" 'BEGIN {print (ra < threshold) ? "1" : "0"}')
        write_active=$(awk -v wa="$write_activity" -v threshold="$LOW_ACTIVITY_THRESHOLD_WRITE" 'BEGIN {print (wa < threshold) ? "1" : "0"}')

        if [ "$read_active" -eq 1 ] && [ "$write_active" -eq 1 ]; then
            low_activity_disks=$((low_activity_disks + 1))
        fi

        total_disks=$((total_disks + 1))
    done

    if [ "$DEBUG" -eq 1 ]; then
        echo "Low activity disks: $low_activity_disks out of $total_disks"
    fi

    # If all disks are under low activity, consider shutting down
    if [ "$low_activity_disks" -eq "$total_disks" ]; then
        if [ $((current_time - last_activity_time)) -ge ${INACTIVE_THRESHOLD} ]; then
            echo "All disks have been under low activity for 30 minutes. Shutting down."
            sudo shutdown -h now
            exit
        fi
    else
        last_activity_time=$(date +%s)
    fi

    sleep ${CHECK_INTERVAL}
done