Connection timeout on SSL with shared hosting

[nathanpgibson]

Hi All, 
Newbie question. I posted this on Stack Overflow but haven't gotten any
replies yet.
https://stackoverflow.com/questions/63391424/why-do-i-get-connection-timeout-on-ssl-even-though-nginx-is-listening-and-firewa

Most/many visitors to my site https://example.org get a connection timeout.
Some visitors get through, possibly ones redirected from http://example.org
or those who've previously visited the site.

I'm trying to determine if this is a firewall issue or an nginx
configuration issue.

Firewall

I'm using UFW as a firewall, which has the following rules:

To                         Action      From
--                         ------      ----
SSH                        ALLOW       Anywhere                  
Nginx Full                 ALLOW       Anywhere                  
80/tcp                     ALLOW       Anywhere                  
443/tcp                    ALLOW       Anywhere                  
SSH (v6)                   ALLOW       Anywhere (v6)             
Nginx Full (v6)            ALLOW       Anywhere (v6)             
80/tcp (v6)                ALLOW       Anywhere (v6)             
443/tcp (v6)               ALLOW       Anywhere (v6) 

I could give some relevant rules from iptables if anyone needs that, but I'd
need some direction on what to look for.

For sudo netstat -anop | grep LISTEN | grep ':443' I get

tcp        0      0 0.0.0.0:443             0.0.0.0:*               LISTEN  
   120907/nginx: worke  off (0.00/0/0)
tcp6       0      0 :::443                  :::*                    LISTEN  
   120907/nginx: worke  off (0.00/0/0)

Not sure what "worke off" means.

nginx

It's a virtual host with the server name myservername.com which serves up
two websites, example.org and example.com/directory. Example.org points to a
docker container running eXist-db. Example.com/directory is serving up a
directory on localhost:8080 proxied from another server where example.com
lives. Example.com/directory is running smoothly on https when I access it
in the browser -- I presume this is because it actually talks to the
example.com host over http.

Example.org and myservername.com both have certs from let's encrypt
generated by certbot.

When I try nmap from my local machine I get some results I can't explain.
Notice the discrepancy between ports 80 and ports 443 and between IPv4 and
IPv6

$ nmap -A -T4 -p443 example.org
443/tcp filtered https

$ nmap -A -T4 -p443 my.server.ip.address
443/tcp filtered https

$ nmap -A -T4 -p443 -6 my:server:ip::v6:address
443/tcp open  ssl/http nginx 1.10.3

$ nmap -A -T4 -p80 example.org
80/tcp open  http    nginx 1.10.3

$ nmap -A -T4 -p80 my.server.ip.address
80/tcp open  http    nginx 1.10.3

My nginx.conf is

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
        worker_connections 768;
        # multi_accept on;
}

http {

        ##
        # Basic Settings
        ##

        client_max_body_size 50M;
        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 65;
        types_hash_max_size 2048;
        # server_tokens off;

        server_names_hash_bucket_size 64;
        # server_name_in_redirect off;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        ##
        # SSL Settings
        ##

        ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;

        ##
        # Logging Settings
        ##

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        ##
        # Gzip Settings
        ##

        gzip on;
        gzip_disable "msie6";

        # gzip_vary on;
        # gzip_proxied any;
        # gzip_comp_level 6;
        # gzip_buffers 16 8k;
        # gzip_http_version 1.1;
        # gzip_types text/plain text/css application/json
application/javascript text/xml application/xml application/xml+rss
text/javascript;

        ##
        # Virtual Host Configs
        ##

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
}

and my nginx server blocks:

server {
        listen 80 default_server;
        listen [::]:80 default_server;

        server_name _ myservername.com;
        return 301 https://myservername.com$request_uri;
}

server {
        # SSL configuration
        #
        listen 443 ssl default_server;
        listen [::]:443 ssl default_server;
        
        server_name _ myservername.com;

        location / {
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_pass http://localhost:8080;
       }

        ssl_certificate
/etc/letsencrypt/live/myservername.com/fullchain.pem;
        ssl_certificate_key
/etc/letsencrypt/live/myservername.com/privkey.pem;
}

server {
        listen 80;
        listen [::]:80;

        server_name example.com www.example.com;

        gzip off;

        location / {
                proxy_set_header Host $host;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_pass http://localhost:8080;
        }
}

server {
       listen 80;
       listen [::]:80;

       server_name example.org www.example.org;
       return 301 https://example.org$request_uri;
}

server {

        # SSL configuration
        #
        listen 443 ssl;
        listen [::]:443 ssl;
        
        server_name example.org www.example.org;

        gzip off;

        location / {
                proxy_set_header Host $host;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_pass
http://docker.container.ip.address:port/exist/apps/example/;
        }

        location /workshop2020/ {
                return 302 http://example.org/forum2020/;
        }


    location /exist/apps/example/ { 
            rewrite ^/exist/apps/example/(.*)$ /$1; 
    }


    ssl_certificate /etc/letsencrypt/live/example.org/fullchain.pem; #
managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/example.org/privkey.pem; #
managed by Certbot

}

Very grateful for any help!!
Nathan

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,289099,289099#msg-289099