Grpc mirroring not working


I have set up grpc-mirroring, but I never see data arrive at the ‘dark’ version.
The same works for http, so I am relatively confident that I have the config right.

Now what is even worse: in 1.0.x the traffic arrives correctly in v1 (the normal target), while in 1.1, as soon as I enable mirroring my go code gets failures like

2019/02/20 16:43:46 could not greet: rpc error: code = DeadlineExceeded desc = context deadline exceeded
2019/02/20 16:43:48 could not greet: rpc error: code = Unavailable desc = upstream connect error or disconnect/reset before headers

Is mirroring supposed to work for grpc? And if not should galley catch that and reject such a mirroring rule?

It the answer is that it should work, then I’ll open an issue with the exact configuration etc.