WebSocket Client's State Not Changing on Network Loss

Question

Working with a WebSocket server using Microsoft.Web.WebSockets.WebSocketHandler where I'm keeping the connected clients in a WebSocketCollection. When the client loses its network connection, at the server the OnClose and OnError methods are not called. Additionally, looking at the specific client in the collection shows that its WebSocket.State is still described as connected. This is on IIS8.

Short of manually sending the client a message and looking for a response, is there another way to determine that the client has dropped of the network? Is there some IIS configuration I'm missing? Thanks.

Answer 1

I was able to solve my problem with two steps. First, I ran the following commands at the prompt to edit the IIS config.

cd \Windows\System32\inetsrv
appcmd unlock config /section:system.webServer/websocket

Then I updated my Web.config with the following.

<system.webServer>
    <webSocket enabled="true" pingInterval="00:00:05" />
<system.webServer />

For IIS Express and VS projects, you have to edit "applicationhost.config" file and change overrideModeDefault="Allow"

<configSections>
        <sectionGroup name="system.webServer">
            ...
            <section name="webSocket" overrideModeDefault="Allow" />
        </sectionGroup>
<configSections>