Nginx Reverse Proxy Configuration

A reverse proxy receives a request and passes it to another service. When a page fails through nginx but works when you call the app directly, first check which part of that path differs.

Start with a minimal route

Confirm the app listens on the address and port nginx uses, then proxy one location to it. Test the configuration with nginx -t before reloading. Keep a known-good version: a generator can give you a starting point, but it cannot know your server’s paths, DNS, certificates, or application requirements.

Follow the headers

An app behind a proxy may need to know the original host and scheme. Host and X-Forwarded-Proto can carry that information, but the app must be configured to trust the right proxy. For WebSockets, the HTTP upgrade requires additional forwarding headers; a normal HTTP page working does not prove the socket will connect.

If the browser shows a TLS error, check the certificate and hostname before editing upstream settings. If nginx returns 502, check whether it can actually reach the upstream.

Related tools

• nginx Config Generator — Build an nginx server block for a static site, a single-page app, PHP or a reverse proxy.
• nginx Reverse Proxy Wizard — Step through domain, upstream, TLS and extras to get a reverse proxy server block.