Reverse Proxy MS SQL with Nginx

Hey it's my first post! Did something nifty today to work around a technical issue I ran into while trying to do my job.

With the COVID-19 thing, I am working from home. The VPN connection we have is a point to point, so I have access to the office LAN. But I don't have access to our data center that is connected to our office via VPN.

To get around this today I had a Linux VM spun up to create a reverse proxy. I first started with HAProxy, and it worked great... till I needed UDP for port 1434. So I switched to Nginx, and was able to proxy both 1433/TCP and 1434/UDP to give me access to the MS SQL server.

Here's the simple Nginx config:

stream {
    upstream dbtcp {
        server db1:1433;
    }

    upstream dbudp {
        server db1:1434;
    }

    server {
        listen 1433;
        proxy_pass dbtcp;
        proxy_connect_timeout 1s; # detect failure quickly
    }

    server {
        listen 1434 udp;
        proxy_pass dbudp;
        proxy_connect_timeout 1s; # detect failure quickly
    }
}

Note that Nginx listens to tcp by default and you only need to denote udp.