A super light-weighted monitoring and alerting tool, if you don't want to configure any of there monitoring tools

upmonitor.sh

#! /bin/bash

ips=("8.8.8.8"
     "baidu.com")

webs=("http://10.0.0.1:8080")

address="user@mails.domain"

for ip in "${ips[@]}"; do
    r=$(/bin/ping -c3 -W1 "${ip}"|grep received|awk '{print $4}')
    if [ $r -lt 3 ]; then
        echo "send mail..."
        echo "${ip} cannot reached"|/usr/bin/mail -s "alert by stb" $address
    fi
done

for web in "${webs[@]}"; do
    r=$(curl -s "${web}"|grep 401|wc -l)
    if [ $r == 0 ]; then
        echo "send mail..."
        echo "${web} cannot reached"|/usr/bin/mail -s "alert by stb" $address
    fi
done