I have encountered this response – "error code: 1003" – when querying a Neo4j instance (running Community 4.4.7, hosted in GCP) from a cloud function (in Cloudflare) using HTTP. The instance itself is up, I can curl it directly from outside of GCP, getting normal query responses back.
I don't see anything in logs – neo4j.log, debug.log, or http.log. I've also searched StackOverflow, public internet, etc. for "neo4j error code 1003", but that didn't turn up anything useful. I found this list of error codes, but none show numeric values: https://neo4j.com/docs/status-codes/current/
What does "1003" represent?
Found the answer: the "1003" error message is coming from Cloudflare itself, not even allowing the request to go out because it's using an IP address. Info here: https://support.cloudflare.com/hc/en-us/articles/360029779472-Troubleshooting-Cloudflare-1XXX-errors...