Final test: Observability: metrics, alerts, logs

Read the output

What answer code did the client get for this request?

$ sudo tail -n 1 /var/log/nginx/error.log
2026/10/22 04:53:29 [error] 1028#1028: *11 connect() failed (111: Connection refused) while connecting to upstream, client: ::1, request: "GET /orders HTTP/1.1", upstream: "http://127.0.0.1:8080/orders"

• A 500
• B 502
• C 504
• D 404