Unexpected connection close

[kidphys]

I have a sockjs web-socket server that transfer data continuously to about 1k clients simultaneously. Occasionally, I see that in the client, the web-socket connection is closed and another connection is open. This is undesirable since my data stream is continuous, and anything disruption is critical.

Is this the normal behavior of a web-socket connection that lives very long?

The deployment model is node server behind a nginx proxy.

[brycekahle]

Network disruptions can happen for any number of reasons. Depending upon perfect operation is probably not wise.

[kidphys]

I know. However this happens quite frequently, and I'm not sure if there is anything wrong on my config or my code. The network's running pretty much fine.

So this is the common event?

[brycekahle]

Impossible for me to know without data. You should capture the close code and reason.

[kidphys]

How should I do that?

There is no error from the server-side. From the client-side, the data stream just stops and our code closes connection 15 secs after the last heartbeat. Basically there's no exception throw.

[brycekahle]

Look for the close or error events on the client and server. If you do maintain a websocket connection the entire time, Chrome lets you inspect the individual frames as well.

[mbratoev]

I am observing a similar issue when I send relatively long series (e.g. 20-30 frames with length around 88000-90000 bytes) of data packets to upload files from client (sockjs v1.1.1) to the server (vertx v3.3.3). Rather often the close event callback is invoked unexpectedly without any obvious reason. If there is an error I would expect at least my onerror callback to be invoked first. Here is what i have in the close event:

{"type":"close","bubbles":false,"cancelable":false,"timeStamp":1474439661639,"wasClean":false,"code":1000,"reason":""}

Maybe the problem does not have anything to do with the volume of the data being transferred but it is rather easy to reproduce it this way. This also happens when I run the client and the server on one and the same machine.

[brycekahle]

Capturing client and server logs will help debugging here.