ansible-infra/playbooks/files/z9/configs/public-reverse-proxy/nginx/acme_challenge.conf

map $host $upstream_acme_challenge_host {
    club-assistant.ccchh.net 10.31.208.10;
    netbox.ccchh.net 10.31.208.29;
    light.ccchh.net 10.31.208.23;
    thinkcccore0.ccchh.net 10.31.242.3;
    thinkcccore1.ccchh.net 10.31.242.4;
    thinkcccore2.ccchh.net 10.31.242.5;
    thinkcccore3.ccchh.net 10.31.242.6;
    zigbee2mqtt.ccchh.net 10.31.208.25:31820;
    esphome.ccchh.net 10.31.208.24:31820;
    proxmox-backup-server.ccchh.net 10.31.208.28;
    status.ccchh.net 10.31.206.15:31820;
    default "";
}

server {
    listen 80 default_server;

    location /.well-known/acme-challenge/ {
        proxy_pass http://$upstream_acme_challenge_host;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        # This is http in any case.
        proxy_set_header X-Forwarded-Proto http;
    }

    # Better safe than sorry.
    # Don't do a permanent redirect to avoid acme challenge pain (even tho 443
    # still should work).
    location / {
        return 307 https://$host$request_uri;
    }
}

server {
    # Listen on a custom port for the proxy protocol.
    listen 8443 ssl http2 proxy_protocol;
    # Make use of the ngx_http_realip_module to set the $remote_addr and
    # $remote_port to the client address and client port, when using proxy
    # protocol.
    # First set our proxy protocol proxy as trusted.
    set_real_ip_from 127.0.0.1;
    # Then tell the realip_module to get the addreses from the proxy protocol
    # header.
    real_ip_header proxy_protocol;

    # ssl_certificate /path/to/signed_cert_plus_intermediates;
    # ssl_certificate_key /path/to/private_key;
    # # verify chain of trust of OCSP response using Root CA and Intermediate certs
    # ssl_trusted_certificate /path/to/root_CA_cert_plus_intermediates;
    ssl_certificate /etc/ssl/certs/public-reverse-proxy.crt;
    ssl_certificate_key /etc/ssl/private/public-reverse-proxy.key;

    # HSTS (ngx_http_headers_module is required) (63072000 seconds)
    add_header Strict-Transport-Security "max-age=63072000" always;

    # replace with the IP address of your resolver
    resolver 127.0.0.1;

    location /.well-known/acme-challenge/ {
        proxy_pass http://$upstream_acme_challenge_host;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        # This is http in any case.
        proxy_set_header X-Forwarded-Proto https;
    }
}