How to prevent browsing by 'ip' address and force use of 'fqdn'?

First of all, gitlab-ce was easy to install. Kudos!
I am trying to set up:

  1. Https (Letsencrypt) OK… got it working

  2. Non default HTTPs port: OK got it working
    external_url 'https://my.fqdn.here:4430'

  3. Prevent access by using IP address only. Force use of ‘FQDN’ to access site: I cannot get it to work. Please help figure this out.
    I tried the following:
    a. change nginx[‘listen_addresses’]
    b. adding dummy nginx config:
    nginx['custom_nginx_config'] = "include /nginx_default/conf/trap.conf;"
    Contents of trap.conf:

    server {
    listen 4430;
    server_name “”;
    return 444;
    }

however, I cannot prevent access using https://<ip address>:4430/ Suggestions?

Hello,

only for the record, Did you reconfigure? gitlab-reconfigure