Checks server uptime on linux machines and raises critical if uptime <= 5 minutes

check_uptime

#!/bin/bash

#####
#
# Author: Dennis Ullrich (request@decstasy.de)
#
# Description:
# Checks server uptime on linux machines and raises critical if uptime <= 5 minutes.
# Made for icinga2 - parameters are not implemented yet.
#
# In global zone:
# object CheckCommand "check_uptime" {
#   import "plugin-check-command"
#   command = [ "/usr/local/nagios/libexec/check_uptime" ]
# }
#
# Service definition:
# apply Service "check_uptime" {
#         display_name = "System Uptime"
#         check_command = "check_uptime"
#
#         import "generic-service"
#         check_interval = 1m
#
#         command_endpoint = host.vars.client_endpoint
#         assign where host.vars.os == "Linux"
# }
#
# Changelog:
# 2019-02-07 V0.1: First release
#
#####

s_to_dhms() {
  ((d=${1}/60/60/24))
  ((h=${1}/60/60%24))
  ((m=${1}/60%60))
  ((s=${1}%60))
  printf "%d days, %02dh:%02dm:%02ds\n" $d $h $m $s
}

read -d . uptime _ </proc/uptime || { echo "Unknown: failed to read /proc/uptime"; exit 3; }

UPTIME="$(s_to_dhms $uptime)"

if [[ $uptime -le 300 ]]; then
  echo "CRITICAL: Machine has been rebootet in the past 5 Minutes! Uptime $UPTIME"
  exit 2
elif [[ $uptime -gt 300 ]]; then
  echo "OK: Uptime $UPTIME"
  exit 0
else
  echo "UNKNOWN: Weird value of $uptime"
  exit 3
fi

# vim: expandtab:ai:ts=2:sw=2:sts=2