# h2 protocol error from reverse proxy Error message: ``` h2 protocol error: http2 error: stream error received: not a result of an error ``` This error appears when the client maintains a long-lived connection through a reverse proxy (nginx, Caddy, HAProxy, etc.) and the proxy closes the connection due to its idle or keepalive timeout. This is expected behaviour. Every reverse proxy has a maximum time it will keep an idle connection open. Once that threshold is reached, the proxy closes the stream, which surfaces as this h2 error on the client side. Increasing the proxy's keepalive or idle timeout reduces how frequently the error appears, but it will still occur eventually. The client handles reconnection automatically. No action is required on the Defguard side. The errors are benign and can be ignored. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.defguard.net/support-1/troubleshooting-guides/core/h2-protocol-error-from-reverse-proxy.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.