# net:ERR\_HTTP2\_PROTOCOL\_ERROR when sending a 409 to Chrome

**URL:** <https://discourse.haproxy.org/t/net-err-http2-protocol-error-when-sending-a-409-to-chrome/4621>\
**Category:** Help!\
**Created:** [December 13, 2019, 9:54am UTC](https://discourse.haproxy.org/t/net-err-http2-protocol-error-when-sending-a-409-to-chrome/4621 "2019-12-13T09:54:14Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Bruno](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Bruno](https://discourse.haproxy.org/u/Bruno)\
**Post date:** [December 13, 2019, 9:54am UTC](https://discourse.haproxy.org/t/net-err-http2-protocol-error-when-sending-a-409-to-chrome/4621/1 "2019-12-13T09:54:14Z")

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Hello,

I work for Cozy Coud and we have found an issue in production, with a weird `net:ERR_HTTP2_PROTOCOL_ERROR` error. After a bit of debugging, we have identified that it happens when Chrome/Chromium/Electron/NodeJS uploads a file in HTTP/2 to haproxy, that proxies this request to our backend in Go (HTTP/1.1 between haproxy and the backend), and that the backend sends a 409 Conflict response before the client has sent the whole file. I’m not sure if it is a bug in haproxy, a bug in Chrome&co, or just me that does something I shouldn’t. I’ve tried to make it simple to reproduce the bug and put that on [https://github.com/nono/bug-haproxy-chrome](https://github.com/nono/bug-haproxy-chrome).

I’d like to know what are your thoughts on this issue.

PS: Discourse has found a [thread on the same subject](https://discourse.haproxy.org/t/chrome-spdy-connection-error/3915), but with no answser.

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**Author:** ![lukastribus](https://avatars.discourse-cdn.com/v4/letter/l/7ea924/32.png) [@lukastribus](https://discourse.haproxy.org/u/lukastribus)\
**Post date:** [December 13, 2019, 1:12pm UTC](https://discourse.haproxy.org/t/net-err-http2-protocol-error-when-sending-a-409-to-chrome/4621/2 "2019-12-13T13:12:53Z")

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Can you file a bug:

> **[haproxy/haproxy](https://github.com/haproxy/haproxy/issues)**
>
> HAProxy Load Balancer's development branch (mirror of git.haproxy.org) - haproxy/haproxy

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**Author:** ![Bruno](https://avatars.discourse-cdn.com/v4/letter/b/c77e96/32.png) [@Bruno](https://discourse.haproxy.org/u/Bruno)\
**Post date:** [December 13, 2019, 1:43pm UTC](https://discourse.haproxy.org/t/net-err-http2-protocol-error-when-sending-a-409-to-chrome/4621/3 "2019-12-13T13:43:30Z")

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Done, it is here: [https://github.com/haproxy/haproxy/issues/410](https://github.com/haproxy/haproxy/issues/410)