Having trouble with Starting connection on shared host

[davbaron]

Hello Sörnt,

After getting things working fine on my local IIS, I have migrated (web-deploy) my web-api site to a shared host (SmarterASP.net). Everything in the web-api site works fine, except SignalR. Using the same Flutter client, when I try to 'start' the connection, I get errors back. Here is the output:

flutter: FINER: 2019-04-16 20:01:37.074299: Starting HubConnection.
flutter: FINER: 2019-04-16 20:01:37.074538: Starting connection with transfer format 'TransferFormat.Text'.
flutter: FINER: 2019-04-16 20:01:37.074753: Sending negotiation request: http://core.totalinsulators.com/activity/negotiate
flutter: FINEST: 2019-04-16 20:01:37.108143: HTTP send: url 'http://core.totalinsulators.com/activity/negotiate', method: 'POST' content: ''
flutter: FINER: 2019-04-16 20:01:37.317341: Selecting transport 'HttpTransportType.WebSockets'
flutter: FINEST: 2019-04-16 20:01:37.317636: (WebSockets transport) Connecting
flutter: FINEST: 2019-04-16 20:01:37.317825: WebSocket try connecting to 'ws://core.totalinsulators.com/activity?id=pqZn4dku_8kKw9ZPf1hQ9A'.
flutter: SEVERE: 2019-04-16 20:01:37.594430: Failed to start the transport 'HttpTransportType.WebSockets': WebSocketException: Connection to 'http://core.totalinsulators.com:0/activity?id=pqZn4dku_8kKw9ZPf1hQ9A#' was not upgraded to websocket
flutter: FINER: 2019-04-16 20:01:37.594694: Selecting transport 'HttpTransportType.ServerSentEvents'
flutter: FINER: 2019-04-16 20:01:37.594864: Sending negotiation request: http://core.totalinsulators.com/activity/negotiate
flutter: FINEST: 2019-04-16 20:01:37.608133: HTTP send: url 'http://core.totalinsulators.com/activity/negotiate', method: 'POST' content: ''
flutter: FINEST: 2019-04-16 20:01:37.734439: (SSE transport) Connecting
flutter: FINER: 2019-04-16 20:01:37.734978: Sending handshake request.
flutter: FINEST: 2019-04-16 20:01:37.735238: Sending message.
flutter: FINEST: 2019-04-16 20:01:37.735467: (SSE transport) sending data.
flutter: FINEST: 2019-04-16 20:01:37.735974: HTTP send: url 'http://core.totalinsulators.com/activity?id=svK4GauaoO4qHqINyMOpSw', method: 'POST' content: '{"protocol":"json","version":1}<…>
flutter: had error starting hub connection: HttpException: Invalid response status code, uri = http://core.totalinsulators.com/activity?id=svK4GauaoO4qHqINyMOpSw

I am guessing this might be a server thing, but would like your opinion before asking the Server people. If it helps, when I did my 'publish', my options were:

Configuration: Release 
Target Framework: netcoreapp2.2
Deployment Mode: Self-Contained
Target Runtime: win-x86

Those were based on recommendations by the host vendor.

Thank you.

[davbaron]

After some back-and-forth with my shared hosting vendor (SmarterASP.net), they tried 'turning off' a security product called SiteGuard. Apparently SiteGuard blocks WebSockets traffic and thus was causing my problem. With SiteGuard 'off', all works fine. I have contacted SiteGuard and asked them if their product can be configured to allow WebSockets traffic, but still provide the other security benefits. In any case, this can be closed.