A reverse proxy can define HTTP headers with the original client IP address, and Nextcloud can use those headers to retrieve that IP address. Nextcloud uses the de-facto standard header ‘X-Forwarded-For’ by default, but this can be configured with the forwarded_for_headers parameter. This parameter is an array of PHP lookup strings, for example ‘X-Forwarded-For’ becomes ‘HTTP_X_FORWARDED_FOR’. Incorrectly setting this parameter may allow clients to spoof their IP address as visible to Nextcloud, even when going through the trusted proxy! The correct value for this parameter is dependent on your proxy software.
Часто в nginx уже ксть lua
https://karlstoney.com/2017/03/09/nginx-lua-script...