I'm tired of waiting for DNS Propagation, so I created this script and put it in crontab. Then I leave my desk for pingpong session...

check-http-resp-code.sh

#!/bin/bash
TOKEN=<your Pushover token>
USER=<generated by Pushover>
MSG="Udah up nih bro!"
URL="url-you-need-to-check"
out=$(curl --write-out "%{http_code}\n" --silent --output /dev/null $URL)
if [ $out = '200' ] ; then
   curl -s \
        -F "token=$TOKEN" \
        -F "user=$USER" \
        -F "message=$MSG" \
        https://api.pushover.net/1/messages

fi
exit 0