HTTP 502: 502 Bad Gateway

What Does HTTP 502 Mean?

HTTP 502 Bad Gateway indicates that the server, while acting as a gateway or proxy, received an invalid response from the inbound server.

Causes and How to Fix HTTP 502

Crashed backend processes (PHP-FPM, Gunicorn, Node.js), out-of-memory errors, or reverse proxy misconfigurations.

SEO & Search Engine Impact

Complete outage. Must be mitigated immediately by restarting backend daemons.

Web Server Configuration (Nginx & Apache)

Configure custom error handling in your web server:

# Nginx Custom Error Handler
error_page 502 /502.html;
location = /502.html {
    root /var/www/html;
    internal;
}