How to make Postgres database available remotely

Question

I am trying to quickly set up a database for some friends to connect to (security, efficiency, and durability are not huge concerns), but I cannot determine what is causing my connection attempts to time out. Pretty much this unanswered question.

PostgreSQL and PGAdmin are created via docker-compose on (let's say) 192.168.1.100.

Everything starts fine. I confirmed that listen_addresses = '*' in the pg conf. Firewall is allowing 5432 and 5050 (pgadmin) to my local network, where my nginx server will pick it up

5050    ALLOW    192.168.1.0/24    # pgadmin
5432    ALLOW    192.168.1.0/24    # postgres

The ngnix server is redirecting a subdomain to the original server's IP and port, like so:

server {
    listen 80;
    server_name pg.mydomain.net;
    location / {
        return 301 https://$host$request_uri;
    }
}
server {
    listen 443 ssl http2;
    server_name pg.mydomain.net;
    proxy_read_timeout 600s;
    location / {
        proxy_pass http://192.168.1.100:5432;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }

        ssl_certificate /etc/letsencrypt/live/mydomain.net/fullchain.pem;
        ssl_certificate_key /etc/letsencrypt/live/mydomain.net/privkey.pem;
}

(this block is boilerplate that I use for all my quick projects, works 90% of the time)

Then on cloudflare I add a CNAME entry for pg.mydomain.net (also one for pgadmin.mydomain.net, which works flawlessly).

But the connection string postgresql://myuser:mypw@pg.mydomain.net:5433/mydb isn't working like it does when I access it by its local ip address directly. I'm thinking the problem lies with nginx. I'm hoping for a solution that allows my users to construct a similarly simple connection string in a Jupyter Notebook.

Answer 1

As was hinted at in the comments but not stated explicitly was that requests to a postgres server are not HTTP/HTTPS, thus it is probably not able to go through nginx.

The reason I (and anyone) would want it to pass through a reverse proxy is to limit the surface area of my network which is exposed to the internet to a single server. It had worked for all kinds of web apps provided by docker containers (including PGAdmin), but this assumption does not hold for data headed to a database.

I say probably not able to go through nginx because it seems like this is what the nginx stream module is for. But since that required a re-compiling and re-installation of nginx just to test a stream{} block, I did not invest the effort.

What ultimately worked is

1. punching a hole in my router for the postgres port, and forwarding that traffic directly to the postgres server (bypassing nginx)
2. setting the DNS CNAME record for the subdomain to be unproxied, whereby it doesn't benefit from Cloudflare hiding my true IP address but at least it does forward traffic correctly.

In the end, my users can connect via any database tool using hostname: pg.mydomain.net, port: 5432, username + password