The PHP 8 release is around the corner. This blog post outlines the steps of installing and configuring PHP 8 on an existing install of Virtualmin on a Ubuntu system. It assumes that Virtualmin has already been installed, and that the ondrej/php PPA has been configured on the system.
Install PHP 8.0 (I currently use FPM on my servers):
apt install php8.0-fpm
As of writing, Virtualmin needs to be patched so that it can pick up PHP 8. Apply this one-line change to your server. Then, run Virtualmin’s config check so that it picks up the new PHP version:
virtualmin check-config
The output should say something like the following:
PHP versions have changed to 7.2, 7.4, 8.0 since last check. Regenerating any missing php.ini files.
Then update all the Virtualmin sites to use the new version:
virtualmin modify-web --all-domains --mode fpm --php-version 8.0
There used to be some quirks as to what PHP versions could be used with PHP-FPM, as configured within the Virtualmin panel. However, since the release of the latest Virtualmin 6.13 at the end of October, it seems to have largely resolved these issues.