Server Error (5xx)

HTTP 502 — 502 Bad Gateway

The server, while acting as a gateway or proxy, received an invalid response from the inbound server it accessed. (Ters proxy (Nginx, Cloudflare, AWS ALB), arkasındaki uygulama sunucusundan (Node.js, Python, PHP-FPM) geçersiz veya boş yanıt aldı.)

Yaygın Nedenler / Common Causes

•Backend Node.js / Python PM2 process crashed or is not running on port.
•Nginx proxy_pass pointing to wrong internal port or IP address.
•Upstream server out of memory (OOM killed).

Spesifikasyon & Kategori

Status Code:502

Category:Server Error (5xx)

RFC Standard:RFC 9110 / HTTP/1.1 & HTTP/2

Nasıl Düzeltilir / Practical Code Solutions

Check PM2 or Systemd Backend Service

Verify if backend application process is running.

pm2 status
pm2 logs backend
systemctl status nginx

Diğer Popüler HTTP Durum Kodları

200 201 204 301 302 400 401 403 404 429 500 503

Frequently Asked Questions

Common Questions About HTTP 502 to RFC Standard

Everything you need to know regarding AST transformations, typing rules, and browser security.

The server, while acting as a gateway or proxy, received an invalid response from the inbound server it accessed. In Turkish: Ters proxy (Nginx, Cloudflare, AWS ALB), arkasındaki uygulama sunucusundan (Node.js, Python, PHP-FPM) geçersiz veya boş yanıt aldı.