How do I troubleshoot the "Server stopped responding" error that I receive when I use Amazon Q Business?

Resolution

When Amazon Q Business can't establish the required network connections, the "Server stopped responding" error occurs. Amazon Q Business uses WebSocket technology over port 8443 to maintain secure communication with endpoints, such as wss://qbusiness.{region}.api.aws:8443/chat. For the web experience to function, port 8443 must be open and accessible to your network.

To check whether port accessibility is causing the issue, systematically test the connection.

Note: If your network uses a VPN or firewall, then make sure to test the connection with the VPN or firewall turned on and turned off.

Test WebSocket connectivity

For macOS or Linux, use the terminal to run the following command:

nc -v qbusiness.us-east-1.api.aws 8443

Example of a successful connection:

Connection to qbusiness.us-east-1.api.aws port 8443 [tcp/pcsync-https] succeeded

For Windows, use Windows PowerShell to run the following command:

Test-NetConnection -ComputerName qbusiness.us-east-1.api.aws -Port 8443

Example of a successful connection:

ComputerName     : qbusiness.us-east-1.api.aws
RemoteAddress    : 34.192.X.X
RemotePort       : 8443
InterfaceAlias   : Wi-Fi
SourceAddress    : 10.0.X.X
TcpTestSucceeded : True

-or-

Use the WebSocket tester on the Pie.host website to test connectivity. Enter your endpoint, and then choose Connect.

A successful network test shows Connection Established in the output. You might also see a Connection closed message that confirms that your client computer can successfully connect to the endpoint on port 8443.

If the test fails, then make sure that port 8443 is open and accessible. Update the settings in your network's VPN, virtual private cloud (VPC), or firewall policies. If you don't have access to the required settings, then contact your network administrator for help.

If the port test is successful but you still receive the error message, then the WebSocket connections might be blocked.

To determine the cause of the error, complete the following steps:

1. Press F12 to open your browser's network console.
2. Make a request in the Amazon Q Business application.
3. Review the console logs for WebSocket connection errors.

A blocked WebSocket connection shows an error message that's similar to the following:

"WebSocket connection to 'wss://qbusiness.us-east-1.api.aws:8443/chat?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=XXXXXXXXXC2MH5KBVFMS%2F20241231%2Fus-east-1%2Fqbusiness%2Faws4_request&X-Amz-Date=20241231T151549Z&X-Amz-Expires=900&X-Amz-failed'"

If you see the preceding message, then contact your network administrator to unblock the network connection.

Related information

Using an Amazon Q Business web experience