[thayne]

> why the http-tunnel feature was removed in this release

From the haproxy 2.0 documentation:

> This mode should not be used as it creates lots of trouble with logging and HTTP processing. And because it cannot work in HTTP/2, this option is deprecated and it is only supported on legacy HTTP frontends. In HTX, it is ignored and a warning is emitted during HAProxy startup.

As for a way to handle this, I believe if you are using an HTTP CONNECT or a websocket (Connection: Upgrade), then haproxy will detect that it is a tunnel, and handle that correctly. If that's not the case, you might be able to use haproxy in tcp mode.

[thedanbob]

There is a bug in 2.2 which prevents websockets (and other tunneling protocols?) from working[0]. Maybe what the OP is running into.

[0] https://github.com/haproxy/haproxy/issues/737