Hello. I have this warning at the end of every page from my installation:
Warning: fsockopen(): unable to connect to tls://collective-access.delisle.duckdns.org:25443:443 (Unknown error) in /var/www/html/ca/app/lib/Controller/Request/RequestHTTP.php on line 660
You can see that my installation uses tcp port 25443. RequestHTTP.php gets the server name from CA_SITE_HOSTNAME which is defined in
app/helpers/post-setup.php: define("CA_SITE_HOSTNAME", isset($_SERVER['HTTP_HOST']) ? $_SERVER['HTTP_HOST'] : '');
$_SERVER['HTTP_HOST'] contains the port in my case. It then adds $vn_port with a value of 443.
$_SERVER['SERVER_NAME'] and $_SERVER['SERVER_PORT'] might be a better choice to find the name and port.