Use proper local CIDR with real IP setting

root/defaults/nginx/site-confs/default.conf.sample

@@ -20,7 +20,7 @@ server {
     root /config/www/nextcloud/;
 
     # display real ip in nginx logs when connected through reverse proxy via docker network
-    set_real_ip_from 172.0.0.0/8;
+    set_real_ip_from 172.16.0.0/12;
     real_ip_header X-Forwarded-For;
 
     # https://docs.nextcloud.com/server/latest/admin_manual/installation/nginx.html#nextcloud-in-the-webroot-of-nginx