As we’ve seen in the last post, zabbix is now monitoring our system, and sends alerts as emails but what if the zabbix server crashes or loose internet connectivity? Here comes @PimOnlineBot.

PimOnlineBot

@PimOnlineBot is a telegram bot that will send you a message when your host is offline.

I have written PimOnlineBot since I could not find any other service like that, the sources are here, and like the sources, the bot is free to use.

Principle of Operation

Using cron and wget, the host periodically tells the bot that it is online. Using that information, the bot will send a message when there is a problem.

Since the resources are not unlimited on this server, messages are only sent for host updating once every 5 minutes or less often.

Setup for one host

Install and activate telegram on your phone.
Open a chat with @PimOnlineBot.
Click the /start button.
Ask for /help.

Setup for monitoring the zabbix server

Login the zabbix’s web UI
Configuration > hosts > zabbix server > Web scenario > Create web scenario
- Scenario tab:
  - Name : PimOnlineBot
  - Application : General
  - Update interval : 5m
- Steps tab:
  - Add (a new step)
    - Name : update status
    - URL : copy the https URL from the /help cron job
    - Parse
    - Required status codes : 200
    - Add (the step)
  - Add (the web scenario)

Setup for non-zabbix server

This one works on any Linux connected to the internet with cron and wget with support for https, tested on raspberry, openwrt(may require some setup for wget+https), ubuntu, … and even on a Lorix One LoraWAN antenna.

Log into your Linux Add the line cron job from the /help command:

5 * * * * wget -q https://pimonlinebot.pignat.org/index.php?uid=UID_FROM_HELP -O /dev/null

Registering the machine

Run this command in the @PimOnlineBot chat, using the uuid from the /help command and your server name:

/register UID_FROM_HELP server-test-setup

If the response is error: server 'XXX' not found, wait for your update command to be run at least once.

The normal reply should be :

success: host server-test-setup (XXX) registered

The /list list the host you’ve registered :

Host server-test-setup (XXX) is up. (update interval : 300 seconds, age : 187 seconds).
Host another-host (YYY) is down (last update : 429613 seconds ago).

Testing (zabbix server version)

On the zabbix web UI:

Configuration > hosts > zabbix server > Web scenario > PimOnlineBot > click on “enable” to disable
wait 6 minutes

receive this message on telegram:

error: Host server-test-setup is offline

Configuration > hosts > zabbix server > Web scenario > PimOnlineBot > click on “disable” to re-enable.
receive this message on telegram:
```
info: Host server-test-setup is online
```

Testing (non-zabbix version)

Edit the crontab, put a # at the beginning of the PimOnlineBot cron job line.
wait 6 minutes

receive this message on telegram:

error: Host server-test-setup is offline

Edit the crontab, remove the # at the beginning of the PimOnlineBot cron job line.
receive this message on telegram:
```
info: Host server-test-setup is online
```

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Question, remark, bug? Don't hesitate to contact me or report a bug.