A proxy or gateway received an invalid response from an upstream server.
# Nginx
location / {
proxy_pass http://backend;
proxy_connect_timeout 60s;
proxy_read_timeout 120s;
proxy_send_timeout 60s;
}Increase proxy timeouts for slow upstream servers.
ObserveOne monitors upstream health and alerts when gateways start returning 502 errors.
Start Monitoring FreeThe server encountered an unexpected condition that prevented it from fulfilling the request.
The server is temporarily unable to handle the request, usually due to maintenance or overload.
A gateway or proxy did not receive a timely response from the upstream server.
The server cannot process the request due to malformed syntax, invalid parameters, or bad encoding.
The request requires authentication. The client must provide valid credentials.