How to change PHP's $_SERVER['SERVER_PORT'] on Apache, behind an Nginx reverse proxy?

Question

I set up Nginx and Apache2 on the same machine with Nginx functioning as a reverse proxy. Nginx uses SSL (at least for 1 of 2 domains: example.com), Apache is used for handling PHP using FPM/FastCGI. I basically followed this tutorial: https://www.digitalocean.com/community/tutorials/how-to-configure-nginx-as-a-web-server-and-reverse-proxy-for-apache-on-one-ubuntu-18-04-server

In step 8, mod_rpaf is used to rewrite Apache's values of REMOTE_ADDR, HTTPS and HTTP_PORT to match the values by the reverse proxy. However, mod_rpaf seems a little dated so I'd like to use mod_remoteip instead. This works fine so far, except for changing the value of $_SERVER['SERVER_PORT']. Here is what phpinfo() on example.com says:

• $_SERVER['HTTPS'] on [as it should be]
• $_SERVER['HTTP_X_FORWARDED_PORT'] 443
• $_SERVER['SERVER_PORT'] 80 [but this is supposed to show 443 as well, according to the tutorial]

My configs:

/etc/apache2/ports.conf (let Apache listen on port 8080):

Listen 8080 <IfModule ssl_module> Listen 443 </IfModule> <IfModule mod_gnutls.c> Listen 443 </IfModule> 

/etc/apache2/sites-available/000-default.conf:

<VirtualHost *:8080> ServerName example.net ServerAdmin webmaster@localhost DocumentRoot /var/www/examplenet/html ErrorLog /var/www/examplenet/error.log CustomLog /var/www/examplenet/access.log combined RemoteIPHeader X-Real-IP RemoteIPInternalProxy 127.0.0.1 SetEnvIf X-Forwarded-Proto "^https$" HTTPS=on </VirtualHost> <VirtualHost *:8080> ServerName example.com ServerAdmin webmaster@localhost DocumentRoot /var/www/examplecom/html ErrorLog /var/www/examplecom/error.log CustomLog /var/www/examplecom/access.log combined RemoteIPHeader X-Real-IP RemoteIPInternalProxy 127.0.0.1 SetEnvIf X-Forwarded-Proto "^https$" HTTPS=on </VirtualHost> 

/etc/nginx/sites-available/default (block requests coming via IP address only and not via domains):

server { listen 80 default_server; listen [::]:80 default_server; return 444; root /var/www/html; index index.html index.htm index.nginx-debian.html; server_name _; location / { try_files $uri $uri/ =404; } } 

/etc/nginx/conf.d/proxy.conf:

server { server_name example.com; listen 80; listen [::]:80; return 301 https://$host$request_uri; } server { listen 80; server_name example.net; access_log /var/log/nginx/examplenet.access.log; gzip on; gzip_comp_level 2; gzip_proxied any; gzip_types text/plain text/html text/css text/xml application/xml application/xml+rss application/xml+atom text/javascript application/x-java> location ~* ^.+\.(jpg|jpeg|gif|png|ico)$ { root /var/www/examplenet/html; #access_log off; gzip off; expires 1d; } location ~* ^.+\.(css|js)$ { root /var/www/examplenet/html; #access_log off; expires 1d; } location ~* ^.+\.(pdf|gz|bz2|exe|rar|zip|7z)$ { root /var/www/examplenet/html; gzip off; } location / { proxy_pass http://127.0.0.1:8080; proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $remote_addr; proxy_set_header X-Forwarded-Proto $scheme; proxy_max_temp_file_size 0; client_max_body_size 10m; client_body_buffer_size 128k; proxy_connect_timeout 90; proxy_send_timeout 90; proxy_read_timeout 90; proxy_buffer_size 4k; proxy_buffers 4 32k; proxy_busy_buffers_size 64k; proxy_temp_file_write_size 64k; } } server { server_name example.com; access_log /var/log/nginx/examplecom.access.log; gzip on; gzip_comp_level 2; gzip_proxied any; gzip_types text/plain text/html text/css text/xml application/xml application/xml+rss application/xml+atom text/javascript application/x-java> location ~* ^.+\.(jpg|jpeg|gif|png|ico)$ { root /var/www/examplecom/html; #access_log off; gzip off; expires 1d; } location ~* ^.+\.(css|js)$ { root /var/www/examplecom/html; #access_log off; expires 1d; } location ~* ^.+\.(pdf|gz|bz2|exe|rar|zip|7z)$ { root /var/www/examplecom/html; gzip off; } location / { proxy_pass http://127.0.0.1:8080; proxy_redirect off; proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header X-Forwarded-Proto $scheme; proxy_set_header X-Forwarded-Port $server_port; proxy_max_temp_file_size 0; client_max_body_size 10m; client_body_buffer_size 128k; proxy_connect_timeout 90; proxy_send_timeout 90; proxy_read_timeout 90; proxy_buffer_size 4k; proxy_buffers 4 32k; proxy_busy_buffers_size 64k; proxy_temp_file_write_size 64k; } listen 443 ssl; # managed by Certbot listen [::]:443 ssl ipv6only=on; # managed by Certbot ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem; # managed by Certbot ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem; # managed by Certbot include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot } 

How can I make PHP set to $_SERVER['SERVER_PORT'] as in the tutorial, making it show 443 instead of 80?