Azure App Service - WebSocket - Reached the end of the file

PauloSergioSimes-3156 1 Reputation point

everything good? I have an application in azure/App Service (WebSocket) that was working normally.

From a week ago I started to have the following error being presented in the log stream when I have to open a websocket connection...

22-10-07T14:49:54 PID[1752] Information Operation=SafetyAccessController.Dispose 2022-10-07T14:49:54 PID[1752] Warning ***** new Open WebSocket Gate: 34B1F7D5DCC9 2022-10-07T14:49:54 PID[1752] Warning ***** Error on WebSocket Gate: 34B1F7D5DCC9 error?:Reached the end of the file state=Aborted status=

Does anyone have any idea what could be causing this?

Haven't modified this program for a few months now and out of nowhere this error started to appear and the client's webSocket connection started to be rejected.

I thank you for your help.

Azure App Service
Azure App Service
Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
6,985 questions
{count} votes

1 answer

Sort by: Most helpful
  1. Swathi Chowdary Manchala 1 Reputation point Microsoft Employee

    App service engineering team has identified that this issue happened after recent upgrade. This happens if the http response 101 Switching Protocol has the Content-Length header.

    Please check if you can remove the Content-Length response header in your application to mitigate this issue as we have seen successful behavior after removing this header.

    This is temporary workaround. Permanent fix will be rolled out soon and it may take 1-2 weeks

    0 comments No comments