Hello, I have an ispconfig 3.2.8p1 server. I install a configuration with apache2. In parallel, I install Zulip chat on that same server. Zulip install script installed nginx. I changed nginx default port going to 5080. I create a website in ispconfig and proxypass zulip. It works. Where I face a difficulty is for LE certificate. In server/lib/classes/letsencrypt.inc.php, I cross that line ;-) Code: $app->log("Could not verify domain " . $temp_domain . ", so excluding it from letsencrypt request.", LOGLEVEL_WARN); Investigating, I discover that when doing curl http://mydomain.tld/.well-known/acme-challenge/le-562876136.8638743.txt This is NGINX which is answering and not APACHE2 I check Ispconfig server setting : Webserver is apache netstat -tunelp | grep 80 says Code: tcp 0 0 0.0.0.0:5080 0.0.0.0:* LISTEN 0 705965 388525/nginx: maste tcp6 0 0 :::5080 :::* LISTEN 0 705966 388525/nginx: maste tcp6 0 0 :::8080 :::* LISTEN 0 2113531 689757/apache2 tcp6 0 0 :::80 :::* LISTEN 0 2113515 689757/apache2 tcp6 0 0 :::8081 :::* LISTEN 0 2148465 689757/apache2 I check /etc/apache2/ports.conf, there is Listen 80 in Apache seems not to listen to tcp... listen only tcp6 ? What should I do without impacting ispconfig configuration to turn back to apache when going to alias /.well-known/acme-challenge/ ?