Check if server is up or notify via Pushover

check_server.sh

#!/bin/bash

api_token=
user_key=

server=10.0.1.3

if nc -z $server 22 2>/dev/null; then
    echo "Server ✓"
else
    echo "Server ✗"
    curl -s \
       --form-string "token=$api_token" \
       --form-string "user=$user_key" \
       --form-string "message=Server is down ✗" \
       https://api.pushover.net/1/messages.json
fi