Updating Raspberry Pi PiHole Servers
Hopefully you were on top of things and have already changed the default login mire that is associated with the Pi. Also hopefully you have enabled telnet on the Pi.
If all these criteria are met, every few weeks I login with telnet and run the following commands:
sudo apt update
sudo apt -yf dist-upgrade
sudo apt-get -y –purge autoremove
sudo apt-get autoclean
pihole -g -up
pihole -up