You may get the following alert in LibreNMS. Basically you need to install python 3 to keep things up to date.
Python 3 is required to run LibreNMS as of May, 2020. You need to install Python 3 to continue to receive updates. If you do not install Python 3 and required packages, LibreNMS will continue to function but stop receiving bug fixes and updates.
Install Python 3
Install Python 3 with yum, or apt if you are on a Debian based distro.
sudo yum install python3
sudo pip3 install -r /opt/librenms/requirements.txt
Verify LibreNMS is updated and working
Run the following commands to make sure that LibreNMS is working correctly and is up to date.
cd /opt/librenms sudo ./validate.php sudo ./daily.sh