I use a NOOELEC dongle for receiving ADS-B signals and sometimes it hangs whereby it stops delivering messages to the dump1090 software. A typical symptom of this fault is when my pi is working fine but I have the “(0 in last 5m)” message within my /var/log/piaware.log file
So I wrote a little bash script which monitors this piaware log file and if it sees any of these messages it sends me a warning email (using ssmtp connected to gmail) with some context and then reboots the device. I run this script every 5 minutes via cron.
The search string could be changed for other items in this or other log files… I added some comments hopefully to decipher the code… Hopefully it is some use to somebody here.