reproducible how? you write the same data and it disconnects? it disconnects after the same amount of time?

a good first step would be to make sure the client and server are the only things involved, if you have some kind of load balancer / proxy in the middle somewhere, try with a direct connection

Yes - there is a load balancer.

I'll try with a direct connection.

Reproducible meaning the same write always yields disconnect, multiple other writes work fine.

It may be on the server... actually - investigating further.

But is there a way that I can see more about the connection on the client short of sniffing the traffic?

you maybe exceeding some max frame size thing

Yeah - I think that's what's happening - I'm getting a large payload when I connect using a python client.

ah, it is a write from the server that is killing it?

Are there settings for this on the aleph side?

Yup

I send a request, then I get a response from the server and it triggers a disconnect; seemingly from the client.

| `max-frame-payload` | maximum allowable frame payload length, in bytes, defaults to `65536`.
   | `max-frame-size` | maximum aggregate message size, in bytes, defaults to `1048576`.

the websocket protocol itself can break up large data over multiple frames, which is why there are two settings there, max-frame-payload is the max for a single frame, and max-frame-size is the max it will allow when recombining multiple frames (I think)

Gotcha.. I think this is the problem - my response is 450k bytes; other payloads that work are 15k bytes...

Yup - this is the guy! I put a limit on the response and now it's working. Thanks for the help here!