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Purpose

In this section, we'll write a really simple script that sends the uptime of our node as a message to our chatbot every hour.
This allows you to precisely monitor your uptime and ensure your node never goes down.
For this, we'll get the uptime from the logs and then send its value to our chatbot using the tg_logbot.sh script we wrote in the previous chapter.

get_uptime.sh​

The script we will use is the following :

$ vim get_uptime.sh
#!/bin/bash
while true
do
        since="24 hours ago" && echo && echo "$(hostname) : Uptime service - sent : $(journalctl --user -u mina -S "$since" | grep 'Sent block with state' | wc -l), failed: $(journalctl --user -u mina -S "$since" | grep 'After 8 attempts, failed' | wc -l)"
        sleep 3600
done

Once launched, this script will loop every hour and return the number of successfull and failed uptime upload retrieved from mina logs.

Example
Hostname : Uptime service - sent : 96, failed: 0

Using get_uptime.sh with tg_logbot.sh​

In order to send the ouput of the script each time it runs (every hour) to telegram, we will do something as easy as pipe the output from get_uptime.sh to tg_logbot.sh

Example
$ ./get_uptime.sh | ./tg_logbot.sh

In order for the script to run in the backbround you can either use nohup along with & such as

$ nohup ./get_uptime.sh | ./tg_logbot.sh &

Or my prefered method, launch the same in a screen session :

$ screen -S uptime
$ ./get_uptime.sh | ./tg_logbot.sh

Then safely detach the screen session with CTRL+A+D.
You can easily reattach the screen session with screen -R uptime thereafter.

You're done !!

Finally, once run, you'll receive every hour right in your telegram chat window with your bot a message with your actual 24 hour uptime.

Uptime value

The uptime retrieved from the script is the splipping 24 hours uptime.
Its value should be 96 (1 upload every 15min, 4 uploads each hour, 4x24=96 uploads a day) which means that you did not miss any uptime upload to the server.
Please note that when a block is produced, an additional entry in the logs is added that will count as a snark upload as well.
It means that if you produced 3 blocks the last 24h, then your score will be 99 and not 96.