Ping server and calc package loss. If loss, sent message to slack channel.

check-server.py

#!/usr/bin/env python
import sys, subprocess, requests

def msg2slack(msg, channel, user):
    url = "<URL>" # your Slack incomming webhook url 
    payload = {"channel": '#%s' % channel,
               "username": user,
               "text": msg,
               "icon_emoji": ":computer:"}
    r = requests.post(url, json=payload)
    # for testing uncomment:
    result = r.text
    print(result)


def main():
    hosts = ['<host1>', '<host2>', ...]

    for hostname in hosts:
        # We will ping a server 10 time and calc package loss.
        # If it loss detected we shoot off a message
        cmd = "ping -c 10 %s | grep -oP '\d+(?=%% packet loss)'"
        proc = subprocess.Popen([cmd % hostname],
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE,
                                shell=True)
        (out, err) = proc.communicate()
        # package loss?
        if int(out)>0 or err:
            # message to slack
            msg2slack(msg="%s cannot be reached" % hostname,
                      channel="mynotes",
                      user="webhookbot")


if __name__=='__main__':
    sys.exit(main())