curl Exit Code 52 in CI: Empty Reply from Server
curl exit code 52 means "empty reply from server" - the server accepted the connection but sent no response.
A step exiting 52 from curl connected but got nothing back, usually because the server closed the connection without answering.
What it means
Exit 52 is curl's CURLE_GOT_NOTHING. The connection succeeded but the server returned zero bytes - it crashed, dropped the connection, or a proxy closed it.
Common causes
- The upstream service crashed mid-request.
- A proxy or load balancer reset the connection.
- The service was still warming up and dropped early requests.
How to fix it
Check the server logs for a crash or restart, and add a readiness wait. An empty reply during warm-up is typically transient and clears on retry.
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