uptime

#!/bin/bash

DEFAULT_WARNING=`expr 60 \* 24` # 24 hours
DEFAULT_CRITICAL=`expr 30` # 30 min
while getopts "h" opt; do
  case $opt in
    h)
      echo "Usage: $0 will alert if uptime is below warning $DEFAULT_WARNING or critical $DEFAULT_CRITICAL minutes"
      echo "Optionally, you can symlink to $0_WARNING_CRITICAL where params are in minutes (e.g. $0_"$DEFAULT_WARNING"_"$DEFAULT_CRITICAL")"
      exit 3
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      ;;
  esac
done

WARNING=`echo $0 | awk -F'_' '{print $2}'`
CRITICAL=`echo $0 | awk -F'_' '{print $3}'`
if [ "$WARNING" == "" ]; then
  WARNING=$DEFAULT_WARNING
fi
if [ "$CRITICAL" == "" ]; then
  CRITICAL=$DEFAULT_CRITICAL
fi

UPTIME_SEC=`cat /proc/uptime | awk '{ print $1 }' | awk -F. '{ print $1 }'`
UPTIME=`expr $UPTIME_SEC / 60`
STATUS=3
MSG="UNKNOWN"

if [ "$UPTIME" -lt "$CRITICAL" ]; then
  STATUS=2
  MSG="CRITICAL - Uptime less than $CRITICAL min ($UPTIME min) [$WARNING/$CRITICAL alerts]"
elif [ "$UPTIME" -lt "$WARNING" ]; then
  STATUS=1
  MSG="WARNING - Uptime less than $WARNING min ($UPTIME min) [$WARNING/$CRITICAL alerts]"
else
  STATUS=0
  MSG="OK - Uptime OK ($UPTIME min) [$WARNING/$CRITICAL alerts]"
fi
echo $STATUS uptime_check uptime=$UPTIME $MSG