nginx caching is enabled in Plesk in Domains > example.com > Apache & nginx Settings.
The option run PHP as is set either to FastCGI application served by Apache or FPM application served by Apache in Domains > example.com > PHP Settings.
When the website is served from nginx cache (the HTTP header
HIT), the initial GET request to the website
"GET / HTTP/2.0" 200 20793"is not logged to the domain access log files
It is the Plesk bug with ID PPPM-9029, which is planned to be fixed in one of the future Plesk updates.
Until the bug is fixed, switch PHP handler on the domain to FPM application served by nginx using the following steps:
Go to Domains > example.com > PHP Settings.
Set the option run PHP as to FPM application served by nginx.
Click OK or Apply to save the changes.
Alternatively, connect to the server using SSH and execute the following command:
# plesk bin subscription --update-web-server-settings example.com -nginx-serve-php true
Connect to the server using SSH.
Get the list of all domains:
# plesk bin domain --list > domains.txt
Edit the file
domains.txtif PHP handler on some domains should not be changed.
Execute the command below for all domains in the file
# cat domains.txt | while read i; do plesk bin subscription --update-web-server-settings $i -nginx-serve-php true; done