icinga2-checks/check_uptime.sh

#!/bin/bash

# Check if the system is Linux or BSD
if uname | grep -q "BSD"; then
  # Get uptime in seconds for BSD
  boot_time_seconds=$(sysctl -n kern.boottime | awk -F'[ ,]' '{print $4}')
  total_uptime_seconds=$(($(date +%s) - boot_time_seconds))
else
  total_uptime_seconds=$(cat /proc/uptime | awk '{print $1}')
  total_uptime_seconds=$(printf "%.0f" "${total_uptime_seconds}")
fi

# Calculate uptime in days, hours, minutes, and seconds
uptime_days=$((total_uptime_seconds / 86400))
uptime_hours=$(((total_uptime_seconds % 86400) / 3600))
uptime_minutes=$(((total_uptime_seconds % 3600) / 60))
uptime_seconds=$((total_uptime_seconds % 60))

# Print the result and perfdata
echo "OK: Uptime is ${uptime_days}d ${uptime_hours}h ${uptime_minutes}m ${uptime_seconds}s | uptime_seconds=${total_uptime_seconds}s;"
exit 0