Install Latest Apache2 On Raspbian
As with most distributions, raspbian does not always come packaged with the latest copy of the apache2 webserver. If you use apache2 to host a service (such as nextcloud) you may want to replace the built-in repo with the latest upstream build from Debian. This ensures critical security fixes are available more quickly.
How to Configure Raspbian
Start by adding the upstream repository and its gpg keys to apt's source list.
Make sure wget is available, then:
sudo wget -O /etc/apt/trusted.gpg.d/apache2.gpg https://packages.sury.org/apache2/apt.gpg
echo "deb https://packages.sury.org/apache2/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/apache2.list
sudo apt update
Then, install the latest apache:
sudo apt install -y apache2
To confirm whether the update worked, run:
apache2 -v
The commandline should print the now-installed apache2 version, which
you can compare to the PPA's webpage. The version on the system
should match the latest version described in the PPA details:
https://launchpad.net/~ondrej/+archive/ubuntu/apache2
You can also restart the server manually if you'd like to make sure the updates are in use:
sudo service apache2 restart